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Solve for b:
-7b + 5 = -6 + 9b
3 | |
\(\frac{11}{16}\) | |
2 | |
-1\(\frac{1}{3}\) |
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.
-7b + 5 = -6 + 9b
-7b = -6 + 9b - 5
-7b - 9b = -6 - 5
-16b = -11
b = \( \frac{-11}{-16} \)
b = \(\frac{11}{16}\)
Solve for b:
b2 - 8b + 7 = 0
2 or -1 | |
1 or 7 | |
2 or -2 | |
-2 or -2 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
b2 - 8b + 7 = 0
(b - 1)(b - 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (b - 1) or (b - 7) must equal zero:
If (b - 1) = 0, b must equal 1
If (b - 7) = 0, b must equal 7
So the solution is that b = 1 or 7
If b = 3 and y = 5, what is the value of -7b(b - y)?
-27 | |
0 | |
-90 | |
42 |
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.)
-7b(b - y)
-7(3)(3 - 5)
-7(3)(-2)
(-21)(-2)
42
Solve for a:
a + 4 = \( \frac{a}{7} \)
-4\(\frac{2}{3}\) | |
-\(\frac{5}{12}\) | |
-3\(\frac{5}{9}\) | |
\(\frac{40}{41}\) |
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.
a + 4 = \( \frac{a}{7} \)
7 x (a + 4) = a
(7 x a) + (7 x 4) = a
7a + 28 = a
7a + 28 - a = 0
7a - a = -28
6a = -28
a = \( \frac{-28}{6} \)
a = -4\(\frac{2}{3}\)
Solve 6a + 7a = 7a + 2x - 8 for a in terms of x.
1\(\frac{1}{12}\)x - \(\frac{1}{12}\) | |
2\(\frac{1}{2}\)x + \(\frac{1}{2}\) | |
5x + 8 | |
2x + 1 |
To solve this equation, isolate the variable for which you are solving (a) on one side of the equation and put everything else on the other side.
6a + 7x = 7a + 2x - 8
6a = 7a + 2x - 8 - 7x
6a - 7a = 2x - 8 - 7x
-a = -5x - 8
a = \( \frac{-5x - 8}{-1} \)
a = \( \frac{-5x}{-1} \) + \( \frac{-8}{-1} \)
a = 5x + 8