Answer:
x = 136/35; y = -⁹/₁₀
Step-by-step explanation:
(1) 7x + 8y = 20
(2) 7x – 2y = 29 Subtract (2) from (1)
10y = -9 Divide each side by 10
(3) y = -⁹/₁₀ Substitute (3) into (1)
7x - 2(-⁹/₁₀) = 29
7x + 18/10 = 29 Subtract 18/10 from each side
7x = 29 - 18/10
7x = (290 - 18)/10
7x = 272/10 Divide each side by 7
x = 272/70
x = 136/35
x = 136/35; y = -⁹/₁₀
Check:
(1) 7(136/35) + 8(-⁹/₁₀) = 20
136/5 - 72/10 = 20
136/5 - 36/5 = 20
100/5 = 20
20 = 20
(2) 7(136/35) – 2(-⁹/₁₀) = 29
136/5 + 18/10 = 29
136/5 + ⁹/₅ = 29
145/5 = 29
29 = 29
Maybe a picture of what the assigment is can help me give you an answer?
It’s option D.) I did a quiz on this !
