| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.11 |
| Score | 0% | 62% |
Solve for b:
b2 + 5b + 1 = 3b + 4
| 1 or -2 | |
| 3 or -3 | |
| 1 or -3 | |
| -5 or -6 |
The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:
b2 + 5b + 1 = 3b + 4
b2 + 5b + 1 - 4 = 3b
b2 + 5b - 3b - 3 = 0
b2 + 2b - 3 = 0
Next, factor the quadratic equation:
b2 + 2b - 3 = 0
(b - 1)(b + 3) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (b - 1) or (b + 3) must equal zero:
If (b - 1) = 0, b must equal 1
If (b + 3) = 0, b must equal -3
So the solution is that b = 1 or -3
If the area of this square is 81, what is the length of one of the diagonals?
| 6\( \sqrt{2} \) | |
| 2\( \sqrt{2} \) | |
| \( \sqrt{2} \) | |
| 9\( \sqrt{2} \) |
To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:
a = s2
so the length of one side of the square is:
s = \( \sqrt{a} \) = \( \sqrt{81} \) = 9
The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:
c2 = a2 + b2
c2 = 92 + 92
c2 = 162
c = \( \sqrt{162} \) = \( \sqrt{81 x 2} \) = \( \sqrt{81} \) \( \sqrt{2} \)
c = 9\( \sqrt{2} \)
If side x = 12cm, side y = 6cm, and side z = 6cm what is the perimeter of this triangle?
| 19cm | |
| 24cm | |
| 27cm | |
| 32cm |
The perimeter of a triangle is the sum of the lengths of its sides:
p = x + y + z
p = 12cm + 6cm + 6cm = 24cm
Simplify (2a)(3ab) + (7a2)(3b).
| 27a2b | |
| 50ab2 | |
| 15ab2 | |
| 27ab2 |
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.
(2a)(3ab) + (7a2)(3b)
(2 x 3)(a x a x b) + (7 x 3)(a2 x b)
(6)(a1+1 x b) + (21)(a2b)
6a2b + 21a2b
27a2b
The endpoints of this line segment are at (-2, -7) and (2, -1). What is the slope of this line?
| \(\frac{1}{2}\) | |
| 1 | |
| -2 | |
| 1\(\frac{1}{2}\) |
The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -7) and (2, -1) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-1.0) - (-7.0)}{(2) - (-2)} \) = \( \frac{6}{4} \)