Question

Phil's age is 7 years more than 1/5 times than Peter's age . Also , 4 times Phil's age is 2 years less than twice Peter's age. If x is Peter's age in years , identify the equation that represents this situation and identify the solution to the equation.

Answer 1

Answer:

x=25

Step-by-step explanation:

we know that "x" is Peter's age

assume that "y" is Phil's age

In the sentence "Phil's age is 7 years more than 1/5 times than Peter's age" are two things: "Phil's age": y and "1/5 times Peter's age": 1/5 x

create equation with these two things

y = 1/5 x

including "7 years more"

many people make a lot of errors with it, they dont know: y+7 = 1/5 x or y=1/5 x + 7 ?

in order to avoid mistakes

read the sentence and point, which: y or 1/5 x is greater and smaller

"Phil's age is 7 years more than ..."

so y is greater, and 1/5 x smaller

y = 1/5 x

greater = smaller

we must add 7 to smaller number to make an equality

greater = smaller + 7

y = 1/5 x + 7

Second sentence:

"4 times Phil's age is 2 years less than twice Peter's age."

Two things: "4 times Phil's age": 4y and "twice Peter's age": 2x

4y = 2x

read the sentence once again

"4 times Phil's age is 2 years less than (...)" , so 4y - smaller, 2x - greater

4y = 2x

smaller = greater

including "2 years less" we add 2 to a smaller number

smaller + 2 = greater

4y + 2 = 2x

Substitute y=1/5 x + 7 to the equation 4y+2 = 2x

$4(\frac15x+7)+2=2x\\ \frac45x+28+2=2x\\ 30=2x-\frac45x\\ 30=1\frac15x\\ \frac65x=30\ \ \ |\cdot 5\\ 6x=150 \ \ \ \ |:6\\ \boxed{x=25}$