body{margin:0;} noscript{z-index: 10000; position: fixed; display: block; height: 100%; width: 100%; background: #fff;} noscript .fa{font-size: 40px; display:block; color: #daa520;} noscript div{margin-top: 6%; padding-left: 20px; padding-right: 20px; text-align: center;} ! You must have JavaScript enabled to use this site.

McGraw Hill Integrated II, 2012

MH

McGraw Hill Integrated II, 2012 View details

5. The Triangle Inequality

Continue to next subchapter

Exercise 57 Page 452

Use the Alternate Exterior Angles Theorem.

x=15 by the Alternate Exterior Angles Theorem

Practice makes perfect

Let's begin by labeling the given angles.

Note that ∠ 1 and ∠ 2 are alternate exterior angles. For lines m and n to be parallel, this pair of angles must be congruent according to the Alternate Exterior Angles Theorem. m∠ 1 = m∠ 2 Finally, we substitute the measures of the angles and solve the equation for x.

m∠ 1 = m∠ 2

m∠ 1= 8x+4, m∠ 2= 9x-11

8x+4 = 9x-11

▼

Solve for x

LHS-8x=RHS-8x

4 = x-11

LHS+11=RHS+11

15 = x

Rearrange equation

x=15

Subchapter links

Exercises p.448-452