As we know y=3/4x-3
Let's put it in the second equation
3/4x-3=1/4x+1
3/4 x -1/4 x = 1+3
2/4 x = 4
X= 4*4/2
x=8
Put x= 8 in first equation
y= 3/4 *8 -3
y=6-3
y=3
Check the answer
3=3/4 *8 -3
3=6-3
3=3
Correct
So(y, x) = (3,8)
Because x=8 and y=3
Multiply the area of the circle by the percentage:
60 square units x 50% = 60 x 0.50 = 30
50% 0f the circle id 30 square units.
Answer: 
Work Shown:
This can be rewritten into 
11.6 because the square root of 135 is 11.61885.... and when you check it is approximately 135 because 11.6 *11.6 = 134.56, which can be rounded to 135
Set up a system of equations.
d + q = 75
.1d + .25q = 14.25
Multiply the first equation by -.1 so that the "d's" will cancel.
-.1d -.1q = -7.5
.1d +.25q = 14.25
Now add the two equations together
.15q = 6.75
divide both sides by .15
q = 45
There are 45 quarters in the jar
