| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.20 |
| Score | 0% | 64% |
Simplify (5a)(4ab) - (2a2)(4b).
| 12a2b | |
| 54ab2 | |
| 28ab2 | |
| 54a2b |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(5a)(4ab) - (2a2)(4b)
(5 x 4)(a x a x b) - (2 x 4)(a2 x b)
(20)(a1+1 x b) - (8)(a2b)
20a2b - 8a2b
12a2b
If BD = 18 and AD = 21, AB = ?
| 13 | |
| 3 | |
| 8 | |
| 10 |
The entire length of this line is represented by AD which is AB + BD:
AD = AB + BD
Solving for AB:AB = AD - BDIf b = -4 and z = -5, what is the value of 2b(b - z)?
| 132 | |
| -30 | |
| -8 | |
| 30 |
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 - z)
2(-4)(-4 + 5)
2(-4)(1)
(-8)(1)
-8
What is the circumference of a circle with a diameter of 15?
| 9π | |
| 7π | |
| 15π | |
| 11π |
The formula for circumference is circle diameter x π:
c = πd
c = 15π
Find the value of b:
6b + x = 5
4b + x = 4
| -2\(\frac{4}{19}\) | |
| 1\(\frac{1}{29}\) | |
| -6 | |
| \(\frac{1}{2}\) |
You need to find the value of b so solve the first equation in terms of x:
6b + x = 5
x = 5 - 6b
then substitute the result (5 - 6b) into the second equation:
4b + 1(5 - 6b) = 4
4b + (1 x 5) + (1 x -6b) = 4
4b + 5 - 6b = 4
4b - 6b = 4 - 5
-2b = -1
b = \( \frac{-1}{-2} \)
b = \(\frac{1}{2}\)