Answer: b+95+34=180, b+129=180, 51
Step-by-step explanation:
b+95+34=180 works because the angles add to form a straight angle.
From this, we can obtain b+129=180 by adding the two constants.
Subtracting 129 from both sides, we get b=51.
Answer:
the first one first the second second and the last last
Step-by-step explanation:
2 1/5 + 22/5 = 4 2/5
9 2/5 + (-5 3/5)= 4 1/5
-8 2/5+9 1/5=1/15
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.
The answer is D.
The others equal 90