| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.31 |
| Score | 0% | 66% |
Which of the following is not a part of PEMDAS, the acronym for math order of operations?
division |
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addition |
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exponents |
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pairs |
When solving an equation with two variables, 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.)
If angle a = 37° and angle b = 49° what is the length of angle c?
| 122° | |
| 94° | |
| 83° | |
| 89° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 37° - 49° = 94°
If the area of this square is 36, what is the length of one of the diagonals?
| 6\( \sqrt{2} \) | |
| 4\( \sqrt{2} \) | |
| \( \sqrt{2} \) | |
| 8\( \sqrt{2} \) |
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 = \( \sqrt{a} \) = \( \sqrt{36} \) = 6
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 = 62 + 62
c2 = 72
c = \( \sqrt{72} \) = \( \sqrt{36 x 2} \) = \( \sqrt{36} \) \( \sqrt{2} \)
c = 6\( \sqrt{2} \)
Solve for x:
x2 - 21x + 69 = -4x - 3
| -6 or -6 | |
| 9 or -7 | |
| 3 or -7 | |
| 8 or 9 |
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:
x2 - 21x + 69 = -4x - 3
x2 - 21x + 69 + 3 = -4x
x2 - 21x + 4x + 72 = 0
x2 - 17x + 72 = 0
Next, factor the quadratic equation:
x2 - 17x + 72 = 0
(x - 8)(x - 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x - 8) or (x - 9) must equal zero:
If (x - 8) = 0, x must equal 8
If (x - 9) = 0, x must equal 9
So the solution is that x = 8 or 9
A cylinder with a radius (r) and a height (h) has a surface area of:
4π r2 |
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π r2h2 |
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π r2h |
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2(π r2) + 2π rh |
A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r2h and the surface area is 2(π r2) + 2π rh.