Question

find value ,while m=3,b=-3



1) 2m+7b
2)2m²-8b
3) -3m+2b-7b²​

Answer 1

Step-by-step explanation:

1) 2m+7b

2×3+7×(-3)

6+(-21)

6-21=-15

2)

${2m}^{2} + 7b \\ 2 \times {3}^{2} - 8 \times ( - 3) \\ 2 \times 9 - ( - 24) \\ 18 + 24 = 42$

3)

$- 3m + 2b - 7 {b }^{2} \\ - 3 \times 3 + 2 \times ( - 3) - 7( { - 3) }^{2} \\ - 9 + ( - 6) - 7 \times 9 \\ - 9 - 6 - 63 \\ = 60$