Hello!
First you to do 65 * 0.20
0.20 is 20% as a decimal
65 * 0.20 = 13
$13 is how much John saves.
To find out how much the skateboard cost you subtract how much he saved by the cost of the skateboard
65 - 13 = 52
The skateboard cost $52
Hope this helps!
Answer:
y=10x
Step-by-step explanation:
it costs 10 dollars for one pound of steak.
Remember (a²-b²)=(a-b)(a+b)
solve for a single variable
solve for y in 2nd
add y to both sides
x²-7=y
sub (x²-7) for y in other equaiton
4x²+(x²-7)²-4(x²-7)-32=0
expand
4x²+x⁴-14x²+49-4x²+28-32=0
x⁴-14x²+45=0
factor
(x²-9)(x²-5)=0
(x-3)(x+3)(x-√5)(x+√5)=0
set each to zero
x-3=0
x=3
x+3=0
x=-3
x-√5=0
x=√5
x+√5=0
x=-√5
sub back to find y
(x²-7)=y
for x=3
9-7=2
(3,2)
for x=-3
9-7=2
(-3,2)
for √5
5-7=-2
(√5,-2)
for -√5
5-7=-2
(-√5,-2)
the intersection points are
(3,2)
(-3,2)
(√5,-2)
(-√5,-2)
Answer:
8pi feet per second
Or, 25.1 feet per second (3 sf)
Step-by-step explanation:
C = 2pi×r
dC/dr = 2pi
dC/dt = dC/dr × dr/dt
= 2pi × 4 = 8pi feet per second
dC/dt = 25.1327412287