Answer:
B
Step-by-step explanation:
∆PQR and ∆SQT are similar, so corresponding sides occur in fixed ratios with one another. This means
SQ / PQ = ST / PR
Solve for x :
8 / ((x + 5) + 8) = (x - 9) / 21
8 / (x + 13) = (x - 9) / 21
168 = (x - 9) (x + 13)
168 = x² + 4x - 117
x² + 4x - 285 = 0
(x + 19) (x - 15) = 0
⇒ x = -19 or x = 15
But x can't be smaller than 9, otherwise ST = x - 9 would be a negative length. So x = 15.
Answer:
x=17/3, y=10/3. (17/3, 10/3).
Step-by-step explanation:
4x-5y=6
2x+5y=-28
-----------------
4x-5y=6
-2(2x+5y)=-2(-28)
--------------------------
4x-5y=6
-4x-10y=56
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-15y=-50
15y=50
y=50/15
y=10/3
4x-5(10/3)=6
4x-50/3=6
4x=6+50/3
4x=18/3+50/3
4x=68/3
x=(68/3)/4
x=(68/3)(1/4)=68/12=17/3
