Answer:
(- 1, 5 )
Step-by-step explanation:
Using the method of substitution.
Given the 2 equations
3x + 2y = 7 → (1)
x - 4y = - 21 → (2)
Rearrange (2) expressing x in terms of y by adding 4y to both sides.
x = 4y - 21 → (3)
Substitute x = 4y - 21 into (1)
3(4y - 21) + 2y = 7 ← distribute and simplify left side
12y - 63 + 2y = 7
14y - 63 = 7 ( add 63 to both sides )
14y = 70 ( divide both sides by 14 )
y = 5
Substitute y = 5 into (3)
x = (4 × 5) - 21 = 20 - 21 = - 1
Solution is (- 1, 5 )
