Answer:
32
Step-by-step explanation:
substitute the given values of a, b and c into the expression:
b² - 2ac = 4² - (2 x 4 x -2)
= 16 - (-16)
= 16 + 16
= 32
TSA of a cuboid= 2(lb+bh+lh)
= 2(5×4+4×1.5+5×1.5)
= 2(20+6+7.5)
= 2× 33.2
= 66.4 square units
3a-10
5x-8