Question

What is the value of x in the equation 4x +8y=40, when y=0,8?

Answer 1

x=8.4

Explanation:

4x +8y=40

replace y as 0.8

4x+8*0.8=40

4x+6.4=40

subtract 6.4 from both sides

4x=33.6

divide by 4

x=8.4

Answer 2

Explanation:

4x + 8y = 40

Simplify the equation

Divide all terms by 4

We have

x + 4y = 10

Make x the subject

x = 10 - 2y

When y = 0.8

Substitute the value of y into the equation

We have

x = 10 - 2(0.8)

x = 10 - 1.6

x = 8.4

Hope this helps you