The sum of 6 times a number and fifteen is forty- two.

Answer 1

Here you have a word problem that needs to be translated into algebraic form. You have all of the information you need in the problem statement to write out and answer it.

The sum of... We know this is an addition problem

six times a number... This tells us that you are multiplying a number (a variable, x, y, z...) 6 times

and fifteen... you are adding 15 to the variable you are multiplying in the step above.

is forty-two... the above information equals 42

Six times a number looks like: 6x. Whenever a number (coefficient) is next to a variable, this indicates Multiplication

(six times a number) (and 15) is 42

6x + 15 = 42

6x +15 = 42.

Since this is an equation, the left side is the same as the right side in value, so whatever operation you perform to one side, you must perform to the other.

Since we have addition, we must undo it by using subtraction. We subtract 15 from both sides and you are left with 6x = 27.

Since we have multiplication on the left, we must undo it by dividing both sides by 6, leaving the variable alone to be equal to the number on the right.

6x ÷ 6 = 1x or just x

27 ÷ 6 equals 4.5

so, x = 4.5

Always check your work to make sure you are correct, by plugging in the answer to the original problem. We know that x= 4.5 so your problem would look like this

6(4.5) + 15 = 42 Parentheses always denote multiplication when a coefficient is next to it.

27 + 15 =42

42 = 42.

Congratulations, it's correct! One of my math teachers in college emphasized that if you can accurately check your answers in math, you can always get a 100%, because you know you did it correctly.