Answer:
A) 684 in^2
Step-by-step explanation:
Since it needs to be painted all around the box we have to find the surface area of the box
The surface area of cuboid is
=2lw+2lh+2hw (l: length, w: width, h: height)
=2×15×12+2×6×15+2×6×12
= 684 in^2
To solve this problem, I am going to use the substitution method. To do this, we use our first equation given (s=4r-1) and substitute this given value for s (4r-1) and substitute it into the second equation so that we have an equation with only one variable. This is modeled below:
s = 4r - 1
6r - 5s = -23
6r - 5(4r-1) = -23
Now, we can solve this equation as we would any other equation, using the order of operations outlined by PEMDAS. To begin, we will distribute the factor of -5 through the parentheses on the left side of the equation.
6r - 20r + 5 = -23
Next, we should combine like terms on the left side of the equation:
-14r + 5 = -23
Next, we should subtract 5 from both sides of the equation to get the variable term alone on the the left side of the equation. We get:
-14r = -28
Finally, we should divide both sides by -14 to get the variable r alone on the left side of the equation.
r = 2
Now that we know that value for the variable r, we can substitute this value into one of our original equations (either one will work, but I am choosing to use the first one):
s = 4r - 1
s = 4(2) - 1
Now, we can find the value for s by using multiplication and then subtraction to simplify the right side of the equation.
s = 8-1
s = 7
Therefore, your answer is s = 7 and r = 2.
Hope this helps!
The factors are
(m-6)(m+6)
Explanation:
Group the first two terms and factor out the common factor:
i.e m(m-6)
Repeat the procedure for terms 3 and 4.
6(m-6)
Regrouping:
m(m-6)+6(m-6)
On factoring out (m-6), we get:
(m-6)(m+6)
Answer: the cyclist must wait for 25 minutes until the hiker catches up.
Step-by-step explanation:
Distance = speed × time
The Cyclist was travelling in the same direction along the same path
as the hiker at a constant rate of 20 miles per hour. If the cyclist stops to wait for the hiker 5 minutes after passing her, then the distance that the cyclist travelled in 5 minutes(5/60 hour) is
20 × 5/60 = 100/60 miles
For the hiker to catch up with the cyclist, she would cover 100/60 miles at a speed of 4 miles per hour.
Time = distance/speed
Time required by hiker to catch up with the cyclist is
(100/60)/4 = 100/240 hour
Converting 100/240 hour to minutes, it becomes
100/240 × 60 = 25 minutes