Step 1) Because the second equation is already solved for xx we can substitute (5y + 2)(5y+2) for xx in the first equation and solve for yy:
3x + y = 43x+y=4 becomes:
3(5y + 2) + y = 43(5y+2)+y=4
(3 xx 5y) + (3 xx 2) + y = 4(3×5y)+(3×2)+y=4
15y + 6 + y = 415y+6+y=4
15y + 6 - color(red)(6) + y = 4 - color(red)(6)15y+6−6+y=4−6
15y + 0 + y = -215y+0+y=−2
15y + y = -215y+y=−2
15y + 1y = -215y+1y=−2
(15 + 1)y = -2(15+1)y=−2
16y = -216y=−2
(16y)/color(red)(16) = -2/color(red)(16)16y16=−216
(color(red)(cancel(color(black)(16)))y)/cancel(color(red)(16)) = -2/16
y = -1/8
Step 2) Substitute -1/8 for y in the second equation and calculate x:
x = 5y + 2 becomes:
x = (5 xx -1/8) + 2
x = -5/8 + (8/8 xx 2)
x = -5/8 + 16/8
x = (-5 + 16)/8
x = 11/8
The Solution Is:
x = 11/8 and y = -1/8
Or
(11/8, -1/8)
