Answer:
432 cm²
Step-by-step explanation:
To find the surface area of a cuboid, there is a formula.
2lw+2lh+2hw
Length is l, height is h, and width is w.
2(12)(8)+2(12)(6)+2(6)(8)
Multiply all the terms.
336+96
Add both the terms.
= 432
The surface area of the open cuboid is 432cm².
Answer:
2 or -2
Step-by-step explanation:
If x² - 8x = -12
Step 1
We find x by solving
x² - 8x = -12
We equate to zero
x² - 8x + 12 = 0
We factorise
x² - 6x - 2x + 12 = 0
x(x - 6) -2(x - 6) = 0
(x - 6) (x - 2) = 0
x - 6 = 0, x = 6
x - 2 = 0, x = 2
x = 6 or 2
Step 2
What is x - 4?
When x = 6
= 6 - 4 = 2
When x = 2
= 2 - 4 = -2
Therefore, x - 4 = 2 or -2
Answer:
a and c
Step-by-step explanation:
Problem 7 is choice B, which is the entire number line shaded in but the value -4 has a hole at this location to mean "exclude this point from the solution set". So basically x can be any number but -4.
Problem 8 is choice C. You have a closed circle (or filled in hole) at -1.5 on the number line. Then you shade to the left of the closed circle to indicate the set of values that are smaller than this endpoint. So n can be -1.5 or it can be smaller than -1.5 (something like -2 or -3, etc).
