Question

Use substitution or elimination to solve each system of equations y=3x
X+y=4

Answer 1

x = 1 & y = 3

Explanation:

y = 3x -----(1)

x + y = 4 -------(2)

sub(1)into(2)

x + 3x = 4

4x = 4

x = 1

sub x=1 into(1)

y = 3(1)

y = 3

Answer 2

(1, 3 )

Explanation:

Given the 2 equations

y = 3x → (1)

x + y = 4 → (2)

Substitute y = 3x into (2)

x + 3x = 4, that is

4x = 4 ( divide both sides by 4 )

x = 1

Substitute x = 1 into (1) for corresponding value of y

y = 3 × 1 = 3

Solution is (1, 3 )