10. 3(6a); a = 3 11. 5d(4); d = -2

12. (5r)(-2); r = -3

13. 3b(8) + (-2)(7c); b = -2, c = 3

14. -4(3s) + 2(-t); s = ½, t = -3

15. 9(4p) - 2(3q) + p; p = -1, q = 4

16. 7(4g) + 3(5h) + 2 (-3g); g = ½, h =⅓

step-by-step explanation:

hans did not square the 40-unit side; he merely multiplied it by 2.   incorrect.

x =-.20752

step-by-step explanation:

4^(x+2)=12

4^(x+2)=12

take the log base 4 on each side

log 4 (4^(x+2) = log 4(12)

we know log b(a^y) = y log b (a)

(x+2) log 4(4) = log 4 (12)

x+2 = log 4 (12)

we know   logb c = loga c/loga b

we want to convert to base 10   so a = 10

by default, we do not write the 10   c = 4   and b = 10

log4 10 = log 12/log 4

log4 10 = log 12/ log 4

x+2 = log 12/ log 4

subtract 2 from each side

x +2 -2 = log 12/ log 4 -2

x = 1.79248125 -2

x =-.20752