When you reflect a point across the x-axis, the x-coordinate remains the same, but the y-coordinate is transformed into its opposite (its sign is changed). If you forget the rules for reflections when graphing, simply fold your paper along the x-axis (the line of reflection) to see where the new figure will be located.
Nickels = x
dimes = x + 4
quarters = x
Value of coins:
nickel = 5 cents
dime = 10 cents
quarter = 25 cents
5x + 10(x + 4) + 25x = 3.20
5x + 10x + 40 + 25x = 320
40x = 320 - 40
40x = 280
x = 280/40
x = 7
There are 7 quarters, 7 nickels and 11 dimes.
see the picture in the attached figure
step 1
find the area of rectangle
A=110*43
A=4730 yd²
step 2
find the area of semicircles
we know that two semicircles is equal to one circle
so
Area of the circle=pi*r²
r=43/2
r=21.5 yd
A=pi*21.5²
A=462.25 *pi yd²-------->1,451.465 yd²
total area=area rectangle + area of circle
total area=4,730+1,451.465---------> 6,181.465 yd²
step 3
find the cost
$0.12 per square yard
6,181.465*0.12=$741.78
therefore
the answer is
$741.78
18x + 20 + x = 10x -3
Combine like terms
19x + 20 = 10x -3
Subtract 20 to both sides because whatever you do on one side you have to do it on the other side:
19x = 10x -23
Subtract 10x
9x = -23
Divide 9 to isolate x:
x = -23/9
Simplify to get a mixed number:
x = -2 5/9
