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:
90 feet
Step-by-step explanation:
320 (1/8) = 40
3/4 (40) = 30 yards
1 yard = 3 feet
30 (3) = 90 feet
Answer:
The answer is Point N
Step-by-step explanation:
Nothing more
Answer:
y=-3/4x-13/2
Step-by-step explanation:
This should be the answer, I am not 100% though
I did y-4=-3/4x(x+14)
Answer:
(x,y,z) -> (2,4,1)
Step-by-step explanation:
-7x + y + z = -9
-7x + 5y - 9z = -3
7x - 6y + 4z = -6
Pick two pairs:
-7x + 5y - 9z = -3
7x - 6y + 4z = -6
and
-7x + y + z = -9
-7x + 5y - 9z = -3
Eliminate the same variable from each system:
-7x + 5y - 9z = -3
7x - 6y + 4z = -6
+ 5y - 9z = -3
- 6y + 4z = -6
<u><em>-1y - 5z = - 9</em></u>
-7x + y + z = -9
-7x + 5y - 9z = -3
-7x + y + z = -9
7x - 5y + 9z = 3
<u><em>-4y - 10z = -6</em></u>
Solve the system of the two new equations:
-1y - 5z = - 9 -> -4 ( -1y - 5z = - 9) -> 4y + 20z = 36
-4y - 10z = -6 -> -4y - 10z = -6 -> -4y - 10z = -6
10z = 30
Thus, z = 3
-4y - 10z = -6
-4y - 10(3) = -6
-4y - 30 = -6
-4y = 24
Thus, y = -6
Substitute into one of the original equations:
-7x + y + z = -9
-7x + (-6) + (3) = -9
7x + -3 = -9
7x = -6
x =
