Answer:
Cross Multiplying.
Step-by-step explanation:
By multiplying each ratio by the second number of the other ratio, you can determine if they are equivalent. Multiply both numbers in the first ratio by the second number of the second ratio. For example, if the ratios are 3:5 and 9:15, multiply 3 by 15 and 5 by 15 to get 45:75.
Hello,
s=48t-16t²
a)
s=0==>16t(3-t)=0==>t=0 or t=3
b)
s>32==>48t-16t²>32===>16(t²-3t+2)<0
Δ=9-8=1
==>16(t-1)(t-2)<0
==>1<t<2 (negative between the roots)
Answer:
x=25
Step-by-step explanation:
43=2x-7 (since the midpoint separate a line into two equal halves)
43+7=2x
50/2=x
25=x
John's hourly rate is 1/8 of the room per hour.
Rick's hourly rate is 1/2 of the room per hour.
Molli's hourly rate would be 3/8 of the room per hour.
It takes Molli 2 2/3 hours to paint the room alone.
Explanation
Since John paints the entire room (100%=1) in 8 hours, he would paint 1/8 of the room in 1 hour.
Since Rick paints the entire room (100%=1) in 2 hours, he would paint 1/2 of it in 2 hour.
We do not yet know Molli's rate, so we will call it x.
We know that 1/8+1/2+x = 1 hour.
We will use 8 as a common denominator:
1/8+4/8+8x/8 = 1
Adding the numerators,
(1+4+8x)/8 = 1
Multiply both sides by 8:
1+4+8x = 8
Add like terms:
5+8x = 8
Subtract 5 from both sides:
5+8x-5=8-5
8x=3
Divide both sides by 8:
8x/8 = 3/8
x = 3/8
Molli's rate is 3/8.
Since she can paint 3/8 of the room in 1 hour, we can set up the equation
3/8x = 1
Divide both sides by 3/8:
3/8x ÷ 3/8 = 1 ÷ 3/8
x = 1/1 ÷ 3/8 = 1/1 × 8/3 = 8/3
x = 2 2/3
This is the amount of time it takes Molli to paint the entire room.
Answer:
The piano is 5.1 feet wide.
