Answer:
c= -2.5-0.5d
Step-by-step explanation:
15=-3(2c+d)
15=-6c+-3d
15+3d=-6c
-2.5-0.5d=c
Answer:
Step-by-step explanation:
|4x-3|=5√(x+4) ⇔ |4x-3|²=5²(√(x+4))² and x+4 ≥ 0
⇔ (4x-3)² = 25(x+4) and x+4 ≥ 0 ( because : /a/² = a²)
⇔16x²-24x+9 = 25x +100 and x+4 ≥ 0
⇔ 16x² -49x - 91 =0 and x+4 ≥ 0 quadratic equation
Δ = (-49)²-4(16)(-91) = 8225
two solution : X1 = (49-√8225)/32 ≅ - 1.3 accept (-1.3+4 ≥ 0)
X2 = (49+√8225)/32 ≅4.37 accept (4.37+4 ≥ 0)
