It’s quicker, easier, and most likely more accurate. But you do learn better doing it by hand but sometimes it can be too much.
8.8 or C is the answer. y= 0.6(8)+4= 8.8
Area of a parallelogram=base x heigth
Data:
base=(2x+3)
heigth=(ax+5)
area of this parallelogram=8x²+bx+15
Therefore:
8x²+bx+15=(2x+3)(ax+5)
8x²+bx+15=2ax²+10x+3ax+15
8x²+bx+15=2ax²+(10+3a)x+15
Then:
8x²=2ax²
a=(8x²)/(2x²)=4
bx=(10+3(4))x
bx=(10+12)x
b=22x/x=22
Answer: a=4 and b=22.