Question

I know the answer to number 7 but I just want to see if you guys know it

Answer 1

Plugging 10 for k in the expression gives us
$2(10)^2+5(10)+1$ We simplify this expression to  $200+50+1=251$
251 is your answer

Answer 2

1.  9(3)+3 = 27+3 = 30
2. 9($8^{4}$) = 9(4096) = 36864
3. 9-6+3 = 6
4. 6(5)+30 = 30+30 = 60
5. 6($8^{3}$) = 6(512) = 3072
6. ($8^{3}$)+84 = 512+84 = 596
7. 200+51 = 251
8. 3(18)+$18^{2}$ = 54+324 = 378
9. 12(24)-36 = 288-36 = 252
10. 4(11+90)+10 = 44+280+10 = 334
11. 8-8 = 0
12.14(95)-1264+1 = 1330-1264+1 = 66+1 = 67