10d+5n=220
divide both sides by 5
2d+n=44
d=13+n
sub 13+n for d in other equatin
2(13+n)+n=44
26+2n+n=44
26+3n=44
minus 26 both sides
3n=18
divide both sides by 3
n=6
sub back
d=13+n
d=13+6
d=19
19 dimes
6 nickles
Answer: x = 6.8
or x = 102/15
Step-by-step explanation:
30x=204
204/30
simplify!
Answer:
x² - 5x = 14
x = -2 or x = 7
Step-by-step explanation:
x² - 5x = 14
x² - 5x - 14 = 0
(x+2)(x-7) = 0
x = -2 or x = 7
Answer:
159.75
Step-by-step explanation:
23.50×5=117.5
117.5+42.25=159.75
