Answer:
Jenna had 25 quarters and 15 dimes.
Step-by-step explanation:
Let Q = the number of quarters and D = the number of dimes.
Then:
1) Q+D = 40 "One week she had 40 coins, all of them dimes and quarters...."
2) 0.25Q+0.1D = $7.75 "...she had a total of $7.75."
Rewrite equation 1) as: D = 40-Q and substitute into equation 2).
2a) 0.25Q+0.1(40-Q) = 7.75 Simplify the left side.
2b) 0.25Q+4-0.1Q = $7.75 Subtract 4 from both sides.
2c) 0.25Q-0.1Q = 3.75 Combine the like-terms on the left side.
2d) 0.15Q = 7.75 Divide both sides by 0.15
2e) Q = 25 and:
D = 40-Q
D = 40-25
D = 15
Jenna had 25 quarters and 15 dimes.
Answer:
y=10x-15
Step-by-step explanation:
with the points given you know x=2 and y=5
make a new point called (x,y)
now use the formula (y-5)/(x-2)=10 (10 being the gradient)
y-5 = 10(x-2)
y-5=10x-20
add 5 to both sides
y-5+5=10x-20+5
y=10x-15
Since this point is located in the fourth quadrant you have to rotate it 270 degrees counterclockwise which would end up being in third quadrant. which means the new point would be (-6,-9)
The answer is
a) 11/15
b) 1/18
