| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.99 |
| Score | 0% | 60% |
Simplify (7a)(8ab) + (7a2)(2b).
| 135ab2 | |
| 70a2b | |
| 135a2b | |
| -42a2b |
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.
(7a)(8ab) + (7a2)(2b)
(7 x 8)(a x a x b) + (7 x 2)(a2 x b)
(56)(a1+1 x b) + (14)(a2b)
56a2b + 14a2b
70a2b
Which of the following is not true about both rectangles and squares?
the area is length x width |
|
the perimeter is the sum of the lengths of all four sides |
|
all interior angles are right angles |
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the lengths of all sides are equal |
A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s2).
If side x = 10cm, side y = 14cm, and side z = 5cm what is the perimeter of this triangle?
| 16cm | |
| 29cm | |
| 20cm | |
| 22cm |
The perimeter of a triangle is the sum of the lengths of its sides:
p = x + y + z
p = 10cm + 14cm + 5cm = 29cm
Find the value of c:
6c + z = -1
8c + z = 8
| -\(\frac{5}{13}\) | |
| -\(\frac{1}{6}\) | |
| 4\(\frac{1}{2}\) | |
| 1\(\frac{5}{21}\) |
You need to find the value of c so solve the first equation in terms of z:
6c + z = -1
z = -1 - 6c
then substitute the result (-1 - 6c) into the second equation:
8c + 1(-1 - 6c) = 8
8c + (1 x -1) + (1 x -6c) = 8
8c - 1 - 6c = 8
8c - 6c = 8 + 1
2c = 9
c = \( \frac{9}{2} \)
c = 4\(\frac{1}{2}\)
Solve for x:
7x - 6 = \( \frac{x}{-6} \)
| -1\(\frac{13}{23}\) | |
| -2\(\frac{2}{7}\) | |
| \(\frac{36}{43}\) | |
| -1\(\frac{1}{5}\) |
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 equal sign and the answer on the other.
7x - 6 = \( \frac{x}{-6} \)
-6 x (7x - 6) = x
(-6 x 7x) + (-6 x -6) = x
-42x + 36 = x
-42x + 36 - x = 0
-42x - x = -36
-43x = -36
x = \( \frac{-36}{-43} \)
x = \(\frac{36}{43}\)