Hello from MrBillDoesMath!
Answer:
72
Discussion:
Total Surface area = area of pyramid base + 4 ( area of triangular face)
In our case this becomes
4*4 + 4( (1/2) (4)(7) ) =
= 16 + (2)(4)(7)
= 16 + 56
= 72
which is the first choice.
Note: the area of a triangular face was computed using (1/2) b h, which in our case is
(1/2) (4) (7)
Thank you,
MrB
Answer: x < -2.861353
Step-by-step explanation:
simplify to: 0.69897x <-2
divide both sides by 0.69897
0.69897/0.69897 < -2/0.69897
so the answer is x < -2.861353
3/8 is bigger than 3/10. In maths 10ths are smaller than 8ths. If both have three parts it means that 3/8 must be bigger
-6(4x + 1) + 7x + 9(x - 3) = 4
-6(4x) - 6(1) + 7x + 9(x) - 9(3) = 4
-24x - 6 + 7x + 9x - 27 = 4
-24x + 7x + 9x - 6 + 27 = 4
-8x + 21 = 4
- 21 - 21
-8x = -17
-8 -8
x = 2.125