Exam Review (2/16)

What is the slope of a line that passes through the points (2, 4) and (1, 8)

• -4

• -1/4

• 6

• 9

Answer explanation

When you see multiplication, you will multiply the coefficients and add the exponents. If you are left with a negative exponent you have to "Flip it and ditch it." In other words, you move the base with a negative exponent to the other side of the fraction, and then get rid of the negative.

Answer explanation

When you see an exponent being raised to the power of another exponent that means you multiply those numbers together. After that, it shows division which means you will subtract those exponents.

Answer explanation

When you see division you will divide the coefficients, and then subtract the exponents. If you are left with a negative exponent you will "Flip it and ditch it." In other words, you will flip the base with a negative exponent to the other side of the fraction, and then get rid of the negative.

Answer explanation

In this problem, we are adding these expressions. There are a few things you need to remember when working with addition. For starters, you can only combine like terms. For example, you can only combine xy with another variable that has a base of xy.

Next, when you add a negative to another negative that will make it more negative. For instance, in this problem when you add -5 with -2 you will get -7.

If you add a positive to a negative number focus on which number is further from zero. That will let you know if the sum of the numbers will be positive or negative. In this problem, -6 is further from zero than 4. That means the sum of the two numbers will be -2.

Answer explanation

To solve this problem, you must start by distributing the 5 into the parenthesis. That means you will multiply 5 times 3x to get 15x, and then you will multiply 5 times 4 to get 20. Next, you will have 15x+20-15. Now, you combine like terms, and you will be left with 15x+5.

5(3x+4)-15

15x+20-15

15x+5

• (2, 12)

• (3, 8)

• There is no solution.

• There are an infinite number of solutions.

Answer explanation

Our primary focus when solving these problems has been getting a variable by itself, and then putting it into the calculator to see where the lines intersect. For this problem, it is easier to solve it out step by step, and remember you can graph the equation by getting either variable by itself.

Solving it out step by step:

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4x+y=20

(Subtract 4x from both sides)

y=-4x+20

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x-2y=-22

(Add 2y to both sides)

x=2y-22

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