The variable "x" equals 7
Answer:14
Step-by-step explanation:
A nickel is 5 cents (20% of dollar)
and a quarter is 25 cents (25% of dollar)
We have given a pile of 42 coins worth of $4.90
Let x be the no nickels and
y be the no of quarter
therefore
x+y=42 -----1
+
=4.90 ---2
Solving 
we get
x=14 & y=28
Therefore no of nickels is 14 & no of quarters is 28
-4.5x-2y=-12.5 and 3.25x-y=-0.75
we first multiply the second equation by -2
(-2)*(3.25x-y=-0.75)=-6.5x+2y=-1.5
add the equation to eliminate the y
so yo get (-4.5x-6.5x)=(-12.5-1.5)
-11x=-11
x=1
now we plug in x into any equation to solve for y
-45x-2y=-12.5 and x=1
(-45*1)-2y=-12.5
-4.5-2y=-12.5
-2y=-12.5+4.5
-2y=-8
y=4
then your answer is x=1 and y=4
Answer:
3 and 7
Step-by-step explanation:
For problems like these I take the largest number in this case 10, and start writing out what 2 numbers would give me 10. 0+10, 1+9, 2+8, 3+7...while doing that I subtract the numbers as well. thus 3+7=10 3-7=-4
The easiest way to think of these is to put them in terms of percentages. Obviously, if you are SAVING 25%, you are SPENDING 75%. So if she SPENDS 13.50, we can easily use the 75% in an equation. $13.50 = .75x, with x being what the shoes cost originally. The .75 indicates that she is spending 75% of what the original cost is. You don't have any examples to pick from, but this is the best way to explain what one of the equations could be. You could also base it on money saved, but the equation is not quite as neat.
