It looks like your equations are
7M - 2t = -30
5t - 12M = 115
<u>Solving by substitution</u>
Solve either equation for one variable. For example,
7M - 2t = -30 ⇒ t = (7M + 30)/2
Substitute this into the other equation and solve for M.
5 × (7M + 30)/2 - 12M = 115
5 (7M + 30) - 24M = 230
35M + 150 - 24M = 230
11M = 80
M = 80/11
Now solve for t.
t = (7 × (80/11) + 30)/2
t = (560/11 + 30)/2
t = (890/11)/2
t = 445/11
<u>Solving by elimination</u>
Multiply both equations by an appropriate factor to make the coefficients of one of the variables sum to zero. For example,
7M - 2t = -30 ⇒ -10t + 35M = -150 … (multiply by 5)
5t - 12M = 115 ⇒ 10t - 24M = 230 … (multiply by 2)
Now combining the equations eliminates the t terms, and
(-10t + 35M) + (10t - 24M) = -150 + 230
11M = 80
M = 80/11
It follows that
7 × (80/11) - 2t = -30
560/11 - 2t = -30
2t = 890/11
t = 445/11
There are no options to choose from but I hope this helps
The price of the discount is $25 x 0.15 = $3.75
The price of the book with discount is $25 - $3.75 = $21.25
Answer:
A) 8
Step-by-step explanation:
Add angles AOB and BOC to get angle AOC.
Since we know the value of AOC is 124 and AOB+BOC=AO
Then (8x+25)+(6x-13)=124.
Combine like terms to get 14x+12= 124.
Solve for x by subtracting 12 from 124, then divide the answer by 14.
Answer:
The volume of the composite figure is:
Step-by-step explanation:
To identify the volume of the composite figure, you can divide it in the known figures there, in this case, you can divide the figure in a cube and a pyramid with a square base. Now, we find the volume of each figure and finally add the two volumes.
<em>VOLUME OF THE CUBE.
</em>
Finding the volume of a cube is actually simple, you only must follow the next formula:
- Volume of a cube = base * height * width
So:
- Volume of a cube = 6 ft * 6 ft * 6 ft
- <u>Volume of a cube = 216 ft^3
</u>
<em>VOLUME OF THE PYRAMID.
</em>
The volume of a pyramid with a square base is:
- Volume of a pyramid = 1/3 B * h
Where:
<em>B = area of the base.
</em>
<em>h = height.
</em>
How you can remember, the area of a square is base * height, so B = 6 ft * 6 ft = 36 ft^2, now we can replace in the formula:
- Volume of a pyramid = 1/3 36 ft^2 * 8 ft
- <u>Volume of a pyramid = 96 ft^3
</u>
Finally, we add the volumes found:
- Volume of the composite figure = 216 ft^3 + 96 ft^3
- <u>Volume of the composite figure = 312 ft^3</u>
