Question

3x+y=8 I really don't understand this and I have tried to get the answer but always end up wrong.

3x-y=4

Answer 1

The solution of the system of the equation is (2, 2)

Explanation:

Let us solve the system of equations

∵ 3x + y = 8 ⇒ (1)

∵ 3x - y = 4 ⇒ (2)

→ Add equations (1) and (2) to eliminate y

∴ (3x + 3x) + (y + -y) = (8 + 4)

∴ 6x + 0 = 12

∴ 6x = 12

→ Divide both sides by 6 to find x

∵
`(6x)/(6)=(12)/(6)`

∴ x = 2

→ Substitute the value of x in equation (1) to find y

∵ 3(2) + y = 8

∴ 6 + y = 8

→ Subtract 6 from both sides

∵ 6 - 6 + y = 8 - 6

∴ y = 2

∴ The solution of the system of the equation is (2, 2)