Factor 65x² - 99x

Factor 65x² - 99x - 50

Here we will show you how to factor the quadratic function 65x² - 99x - 50 using the box method. In other words, we will show you how to factor 65x squared minus 99x minus 50 (65x^2 - 99x - 50) using the box method. It is a 5-step process:

Step 1: The standard form of a quadratic equation is ax² + bx + c. We start by labeling the different parts of our equation 65x² - 99x - 50, like this:

a = 65
b = -99
c = -50

Step 2: Next, we need to draw a box and divide it into four squares:

-25	-125x	-50
13x	65x²	26x
	5x	2

We put 65x² (a) in the bottom left square and -50 (c) in the top right square, like this:

-25	-125x	-50
13x	65x²	26x
	5x	2

Step 3: In order to fill in the other two squares, we need to do some math. We have to find two numbers that multiply together to give us the product of 65 times -50 (a × c), and add together to equal -99 (b).

More specifically, 65 times -50 is -3250. Therefore, we need to find the two numbers that multiply to equal -3250, and add to equal -99.

? × ? = -3250
? + ? = -99

After looking at this problem, we can see that the two numbers that multiply together to equal -3250, and add together to equal -99, are -125 and 26, as illustrated here:

-125 × 26 = -3250
-125 + 26 = -99

Now, we can fill in the last two squares in our box with -125x and 26x. Place -125x in the upper left square, and place 26x in the lower right square.

-25	-125x	-50
13x	65x²	26x
	5x	2

Step 4: Next, we need to find four final numbers to finish factoring our equation. We can see that our box is a 2 x 2 table made up of rows and columns.

Our goal is to find the numbers that, when multiplied together, result in the products in each square. We can do this by finding the greatest common factor in each row.

Let’s look at the top row. We have the terms -125x and -50. The greatest common factor of -125x and -50 is -25. Therefore, we write -25 to the left of the top row. You can see it here in the color green:

-25	-125x	-50
13x	65x²	26x
	5x	2

Next, let’s look at the bottom row. We have the terms 65x² and 26x. The greatest common factor of 65x² and 26x is 13x. Therefore, we write 13x to the left of the bottom row. You can see it here in the color blue:

-25	-125x	-50
13x	65x²	26x
	5x	2

To find the values below the table, we first divide 65x² by 13x (labeled in blue). This gives us 5x.

65x² ÷ 13x = 5x

You can see this value colored in orange below:

-25	-125x	-50
13x	65x²	26x
	5x	2

Next, we divide 26x by 13x (labeled in blue). This gives us 2.

26x ÷ 13x = 2

You can see this value colored in purple below:

-25	-125x	-50
13x	65x²	26x
	5x	2

Step 5: Now we have all of the information we need to finish factoring the equation. The values outside of the box are used to factor 65x² - 99x - 50. You simply put the values on the left in one set of parentheses, and the values below in another set of parentheses, to get the answer:

(13x - 25)(5x + 2)

That’s it! Now you know how to factor the equation 65x² - 99x - 50.

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