Use the substitution method . . . 13x - 2y = 70 2x - 2y = 4
13x – 2y = 70
2x – 2y = 4 —> –2y = 4 – 2x
2y = 2x – 4 <— substitute this into the other equation
13x – (2x – 4 ) = 70
13x – 2x + 4 = 70
11x = 66
x = 6
2x – 2y = 4
12 – 2y = 4
–2y = –8
y = 4
check answer
Does (13)(6) – (2)(4) equal 70 ?
78 – 8 = 70 true
.