So you will need to solve for x and y before evaluating 2x+y....
2x-y=9, y=2x-9 now this will make 4x^2-y^2=171 become:
4x^2-(2x-9)^2=171
4x^2-(4x^2-36x+81)=171
36x-81=171
36x=252
x=7, now we can use 2x-y=9 to solve for y...
2(7)-y=9
14-y=9
-y=-5
y=5
now we know that x=7 and y=5, 2x+y becomes:
2(7)+5
14+5
19
Answer:
5 and 25
Step-by-step explanation:
let the son's age be x then the father's age is x + 20
In 5 years
son = x + 5 and father = x + 20 + 5 = x + 25
Then
x + 25 = 3(x + 5) ← father is three times as old as son
x + 25 = 3x + 15 ( subtract x from both sides )
25 = 2x + 15 ( subtract 15 from both sides )
10 = 2x ( divide both sides by 2 )
5 = x and x + 20 = 5 + 20 = 25
si=on is 5 and father is 25
Answer:
x=-4
Step-by-step explanation:
Since we know that the equation will be x= we will just have to take the x value of the coordinate point and that would be the x so in this case the x is -4 so the equation would be x=-4
Decimal form
-0.015625
Exact form
-1/60
Negative one over sixty
