Answer:
y=-4, x=1
Step-by-step explanation:
2x-y=6 x+y=-3
2(-3-y)-y=6 x=-3-y
-6-2y-y=6 x=-3+4
-3y=12 x=1
y=-4
Answer:
50 nickels, 20 quarters.
Step-by-step explanation:
System of equations (q = # of quarters, n = # of nickels):
<em>q + n = 70, 0.25q + 0.05n = 7.50</em>
the first equation can be changed to q = 70 - n, so we are able to <em>substitute q with 70 - n</em>.
So, it will look like <em>0.25*70 - 0.25n + 0.05n = 7.50</em>. This can be simplified to <em>0.2n = 10</em>, which means that n = 50.
Knowing that we can solve <em>q + 50 = 70</em>, which means that q = 20.
Answer: 0.238853503185
(I obviously used a calculator.)
If you rounded this answer, it would be 0.24. Hope this helps!
Answer:
0.85
Step-by-step explanation:
