We substitute in c using 9, it will be as follows:
5 ×[(-6×9)+4] = 5 × (-54+4) = 5 × (-50) = -250
Answer:
m∠A ≈ 43°
m∠B ≈ 55°
mBC ≈ 20
Step-by-step explanation:
Law of Sines: 
Step 1: Find m∠B

Step 2: Solve for ∠B
29sinB = 24sin82°
sinB = 24sin82°/29
B = sin⁻¹(24sin82°/29)
B = 55.038°
Step 3: Find m∠A
180 - (55.038 + 82)
180 - 137.038
m∠A = 42.962°
Step 4: Find BC

Step 5: Solve for BC
29sin42.962° = BCsin82°
BC = 29sin42.962°/sin82°
BC = 19.9581
180- 113 = 67
180- 67= 113
<5= 67
<2=113
If you were to make both x's equivalent, you'd have to multiply the first equation by 2 to get rid of the coefficient, 1/2. However, you'd have to multiply 2 onto -8 as well, therefore the equation would turn into x - 16 = 18. That is not equivalent to x - 8 = 18.