| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.82 |
| Score | 0% | 56% |
Find the value of a:
-a + y = 9
-5a - 7y = -7
| -4\(\frac{2}{3}\) | |
| -\(\frac{4}{13}\) | |
| -1\(\frac{4}{21}\) | |
| -\(\frac{1}{9}\) |
You need to find the value of a so solve the first equation in terms of y:
-a + y = 9
y = 9 + a
then substitute the result (9 - -1a) into the second equation:
-5a - 7(9 + a) = -7
-5a + (-7 x 9) + (-7 x a) = -7
-5a - 63 - 7a = -7
-5a - 7a = -7 + 63
-12a = 56
a = \( \frac{56}{-12} \)
a = -4\(\frac{2}{3}\)
The dimensions of this cube are height (h) = 3, length (l) = 2, and width (w) = 5. What is the surface area?
| 62 | |
| 82 | |
| 40 | |
| 108 |
The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):
sa = 2lw + 2wh + 2lh
sa = (2 x 2 x 5) + (2 x 5 x 3) + (2 x 2 x 3)
sa = (20) + (30) + (12)
sa = 62
If a = c = 8, b = d = 5, and the blue angle = 51°, what is the area of this parallelogram?
| 9 | |
| 40 | |
| 18 | |
| 20 |
The area of a parallelogram is equal to its length x width:
a = l x w
a = a x b
a = 8 x 5
a = 40
Solve for y:
-6y + 9 > 7 + 7y
| y > \(\frac{3}{4}\) | |
| y > 7 | |
| y > -\(\frac{1}{2}\) | |
| y > \(\frac{2}{13}\) |
To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the > sign and the answer on the other.
-6y + 9 > 7 + 7y
-6y > 7 + 7y - 9
-6y - 7y > 7 - 9
-13y > -2
y > \( \frac{-2}{-13} \)
y > \(\frac{2}{13}\)
If b = -2 and x = -3, what is the value of -2b(b - x)?
| 4 | |
| 42 | |
| 6 | |
| -567 |
To solve this equation, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
-2b(b - x)
-2(-2)(-2 + 3)
-2(-2)(1)
(4)(1)
4