McGraw Hill Glencoe Algebra 1, 2012
MH
McGraw Hill Glencoe Algebra 1, 2012 View details
5. Solving Quadratic Equations by Using the Quadratic Formula
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Exercise 49 Page 588

Practice makes perfect
a We want to write an equation for the area of the section with text. The dimensions of this section are and as shown below.
Bartolo wants the area of this section to be three-fourths of the so it has an area of
One side of the equation is the other side is the expression for the area of the section, the times the
b We need to rewrite the equation in standard form to be able to use the Quadratic Formula.
Multiply parentheses
Now, we can identify the values of and
We see that and Let's substitute these values into the Quadratic Formula.
Simplify right-hand side
The solutions for this equation are Let's separate them into the positive and negative cases.

Using the Quadratic Formula, we found that the solutions of the given equation are and

c The margins of the poster should be on the sides, on the top, and on the bottom.
Note that the other solution makes the lengths negative.