Question

3. Evaluate the following.​

Answer 1

Step-by-step explanation:

1.) Given n = -2

So, 5n²+5n-2

= 5×(-2)²+5×(-2)-2

= 5×4-10-2

= 20-12

= 8

2.) Given a = -2

So, 2a³+3a²+2a-7

= 2×(-2)³+3×(-2)²+2×(-2)-7

= 2×(-8)+3×4-2-7

= -16+12-7

= -11

3.) Given a = 3 , b = 2

So, 7a-4b

= 7×3-4×2

= 21-8

= 13

4.) Given y = 1

also y²+y-a = 3

So, 1²+1-a = 3

1+1-a = 3

2-a = 3

a = 2-3 = -1