Answer:
D. 14448
Step-by-step explanation:
S = Base area + lateral surface area
=2*(1/2*(56*42)) + (56+42+70)*72
= 2352 + 12096
= 14448
|DF| = |DE| + |EF| |DF| = 9x -36 |DE| = 47 |EF| = 3x+10 Substitute: 9x - 39 = 47 + 3x + 10 9x - 39 = 3x + 57 |+39 9x = 3x + 96 |-3x 6x = 96 |:6 x = 16 Put the value of x to the equation |EF| = 3x + 10 |EF| = (3)(16) + 10 = 48 + 10 = 58 Answer: |EF| = 58
Read more at Answer.Ya.Guru – https://answer.ya.guru/questions/4046336-if-df-9x-39-find-ef.html
Answer: C is correct, No solution
Step-by-step explanation:
Let’s simplify the second equation,
8x-4y=-20
We can divide the whole equation by 4...
8x/4-4y/4=-20/4
Which becomes....
2x-y=-5
Now let’s move things around to see if it’s the same equation as the one on top...
-y=-2x-5
y=2x+5
Now we need to solve the systems...
y=2x-5
y=2x+5
Since their slopes are both 2 and their y-intercepts are not identical, the answer is no solution. The two lines will continue on without ever crossing because they have the same slope.
16/21 is your answer
You can take a 2 out of both numbers to get your answer
I hope this helped! :)
