Question

In 6 years, Jonathan's age will be twice Alfredo's age. What is Jonathan's current age if three years ago he was three times Alfredo's age?

155

likes

773 views

Answer to a math question In 6 years, Jonathan's age will be twice Alfredo's age. What is Jonathan's current age if three years ago he was three times Alfredo's age?

$Expert avatar$

Jett

4.7

92 Answers

\begin{cases} x + 6 = 2(y + 6) \\x - 3 = 3(y - 3) \end{cases}

1. De la primera ecuación:

x + 6 = 2y + 12

x - 2y = 6

2. De la segunda ecuación:

x - 3 = 3y - 9

x - 3y = -6

3. Resolvamos el sistema de ecuaciones

Restando las dos ecuaciones:

(x - 2y) - (x - 3y) = 6 - (-6)

y = 12

4. Sustituyamos

y = 12

en una de las ecuaciones para encontrar

x - 2y = 6

x - 2(12) = 6

x - 24 = 6

x = 30

Por lo tanto, la edad actual de Jonathan es:

x = 15 \, años

Frequently asked questions (FAQs)

What is the value of 2π/3 radians in degrees?

What is the domain of the logarithmic function f(x) = log x / f(x) = ln x?

What is the derivative of f(x) = sin(x) + 3x^2 - ln(x)?

New questions in Mathematics

a ferry travels 1/6 of the distance between two ports in 3/7 hour. The ferry travels at a constant rate. At this rate, what fraction of the distance between the two ports can the ferry travel in one hour.

P is a polynomial defined by P(x) = 4x^3 - 11×^2 - 6x + 9. Two factors are (x - 3) and (x + 1). Rewrite the expression for P as the product of linear factors.

find all matrices that commute with the matrix A=[0 1]

78 percent to a decimal

Log5 625

determine the polynomial F of degree 2 that interpolates. f at points (0;1) (2;5) (4;6). calculate F(0.8). Note: Using the polynomial expression with difference operator.

6-35 A recent study by an environmental watchdog determined that the amount of contaminants in Minnesota lakes (in parts per million) it has a normal distribution with a mean of 64 ppm and variance of 17.6. Assume that 35 lakes are randomly selected and sampled. Find the probability that the sample average of the amount of contaminants is a) Greater than 72 ppm. b) Between 64 and 72 ppm. c) Exactly 64 ppm. d) Greater than 94 ppm.

During a fishing trip Alex notices that the height h of the tide (in metres) is given by h=1−(1/2)*cos(πt/6) where t is measued in hours from the start of the trip. (a) Enter the exact value of h at the start of the trip in the box below.

Equine infectious anemia (EIA) is considered the main infectious disease in Brazilian equine farming, for which there is no effective vaccine or treatment. It is caused by a retrovirus of the genus Lentivirus, which affects horses, donkeys and mules and is transmitted in nature mainly by hematophagous insects of the genus Tabanidae. Researchers analyzed the records of 9,439 equids from Acre, submitted to the agar gel immunodiffusion test (AGID) for equine infectious anemia (EIA), between 1986 and 1996. Of these, 6199 tested positive for equine infectious anemia (EIA) . Knowing that the age of AIE-positive horses follows a Normal distribution with a mean of 5 years and a standard deviation of 1.5 years, determine the expected number of AIE-positive horses in the Acre sample that will be aged less than or equal to 3 years. ATTENTION: Provide the answer to exactly FOUR decimal places.

Two minus log 3X equals log (X over 12)

Determine a general formula (or formulas) for the solution to the following equation. Then, determine the specific solutions (if any) on the interval [0,2π). cos30=0

In a physics degree course, there is an average dropout of 17 students in the first semester. What is the probability that the number of dropouts in the first semester in a randomly selected year has between 13 and 16 students?

15.A newly married couple purchased a home with a $123710 down payment. They financed the remaining balance of the home with a mortgage. Their payments were $15395 at the end of every six months for 23 years and the interest rate was 10.6%, compounded semi-annually. How much did they purchase their home for. Enter to the nearest cent (two decimals). Do not use $ signs or commas in the answer.

Write an expression using compatible numbers that can be used to estimate the quotient 629\86

Find the set of points formed by the expression 𝜋<|𝑧−4+2𝑖|<3𝜋.

To verify that a 1 kg gold bar is actually made of pure gold, a dynamometer is used to record the weight of the bar submerged in water and out of water. a) What would be the value of the weight of the ingot recorded by the dynamometer out of the water? b) What magnitude of thrust does the ingot receive when it is submerged? c) What would the weight of the ingot have to be when it is submerged? Data Pagua = 1000 kg/m³ Pagua= 19300 kg/m³

2 - 6x = -16x + 28

Write decimal as the fraction 81/125 simplified

Slope (7,3) and (9,5)

Find the number of liters of water needed to reduce 9 liters of lotion. shave containing 50% alcohol to a lotion containing 30% alcohol.

In 6 years, Jonathan's age will be twice Alfredo's age. What is Jonathan's current age if three years ago he was three times Alfredo's age?

Answer to a math question In 6 years, Jonathan's age will be twice Alfredo's age. What is Jonathan's current age if three years ago he was three times Alfredo's age?

You might be interested in