Question

(08.03)A system of equations is given below:

y = 4x − 3
2x + 7y = 41

Which of the following steps could be used to solve by substitution?

Answer 1

Plug in y for the bottom equation.
2x+7(4x-3)=41
2x+28x-21=41
30x-21=41
30x=62
x=2.07
Plug in x to get y value.
y=4(2.07)-3
y=8.28-3
y=5.28
Check answers.
2(2.07)+7(5.28)=41
4+36=41
41=41
(2.07,5.28)
I rounded my answers

Answer 2

Answer with Step-by-step explanation:

y = 4x − 3

2x + 7y = 41

Putting equation first in equation second

2x+7(4x-3)=41

⇒ 2x+28x-21=41

⇒ 30x=41+21

⇒ 30x=62

⇒ x=62/30

⇒ x=2.06

Putting value of x in first equation

y=4×2.06-3

⇒ y=5.24

Hence, steps that could be used to solve by substitution is:

substituting equation first into second