# Tutor profile: David A.

## Questions

### Subject: Pre-Algebra

If the formula p=kt, find the value of p when k = 36 and t = 24.

This problem would be solved using the pre-Allegra concept of substitution. We know the values of 2 out of the 3 variables listed in the problem. We also know that in an algebraic sentence, when variables are next to each other without any sign between them, that signifies the operation of multiplication. So, before we multiply with the numbers, we can re-write the sentence to show what our operation will be: P = k x t When we substitute the numbers into the algebraic equation, we can carry out the operation and multiply to get our final answer: P = 36 x 24 P = 864

### Subject: Basic Math

A soccer team played 160 games and won 65 percent of them. How many games did they win?

The soccer team had 160 games total and since they won 65 percent of them, we need to determine what is 65 percent of 160 games. We can rewrite this problem into a math sentence knowing that percent means a number out of 100 and the word “of” means to multiply: 65/100 x 160 We can either multiple the fraction out, or change the fraction to it’s decimal form, 0.65, and then multiply it out as follows: 0.65 x 160 = 104 Therefore, the soccer team won 104 being that 104 is 65 percent of 160.

### Subject: Algebra

Solve for X: 3x + 7 = 4x - 5

First you have to get all the x terms to one side of the equal sign and all the number terms to the opposite side of the equal sign. We will move 4x to the left of the equal sign. To do this, we do the inverse operation (think opposite) of what the term 4x is, which is a plus or positive 4x. The opposite of 4x is a negative, or minus, 4x: 3x - 4x + 7 = -5 Then you have to move the + 7 term to the right of the equal sign. We do this by it’s inverse which would be -7: 3x - 4x = -5 - 7 Then we combine like terms on both sides of the equal sign: -x = -12 We finish by having to remove the negative sign in front of the x. That -x term represents an invisible coefficient of 1 in front of the x, which could be written as: -1x = -12 We have to use the inverse of the coefficient of -1x to move it to the other side of the equal sign. -1x can also be read as -`1 times x, and the inverse of multiplication is division. We will then divide both sides of the equal side by a -1, thus giving us our final answer: X = 12