<span>a=7b+8c+9d-10
a = 8c + 16d - 10
solve for c then
8c = a - 16d + 10
c = (</span>a - 16d + 10) / 8
or
c = a/8 - 2d + 5/4
When you write it as an inequality you get x + 19 ≈ 8.2 and when you solve it it should look like x + 19 ≈ 8.2
19 ≈ - <u>19
</u> x ≈ -10.8<u>
</u>
At D point in the bottom then up and to the right upper corner to Letter B
3x - 2y = 8 +
===》 46x = 16
43x + 2y = 8
x = 16/46
x = 8/23
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3x - 2y = 8
3(8/23) - 2y = 8
24/23 - 2y = 8
2y = 24/23 - 8
y = 12/23 - 4
y = 12/23 - 92/23
y = - 80/23