The sum of 38 and twice a number x is 124. What is -2x - 5?
A. -101
B. -91
C. 46
D. 86
Let's solve the equation: 38 + 2x = 124
First, subtract 38 from both sides: 2x = 124 - 38 -> 2x = 86
Next, divide both sides by 2: x = 43
Now, let's find -2x - 5: -2(43) - 5 = -86 - 5 = -91
Therefore, the answer is B. -91
Let's break down the problem step-by-step:
Step 1: Write the given information as an equation.
The sum of 38 and twice a number x is 124. So, we can write the equation as:
38 + 2x = 124
Step 2: Solve the equation for x.
To solve the equation, we need to isolate the variable x.
Subtract 38 from both sides of the equation:
2x = 124 - 38
2x = 86
Divide both sides of the equation by 2:
x = 86/2
x = 43
Step 3: Plug in the value of x to find -2x - 5.
We are asked to find -2x - 5.
Substitute the value of x into the expression:
-2(43) - 5
= -86 - 5
= -91
So, the answer is B. -91
To solve this problem, we need to set up an equation based on the given information.
Let's start by translating the problem into an equation.
We know that the sum of 38 and twice a number x is 124. Mathematically, we can write this as:
38 + 2x = 124
Now, we can solve this equation to find the value of x.
Subtract 38 from both sides of the equation to isolate 2x:
2x = 124 - 38
Simplify the right side:
2x = 86
Now, divide both sides of the equation by 2 to solve for x:
x = 86 / 2
Simplify the right side:
x = 43
Now that we have the value of x, we can substitute it into the expression -2x - 5 to find the answer:
-2(43) - 5
Simplify the expression:
-86 - 5
Combine like terms:
-91
Therefore, the correct answer is B. -91.