15x 2 7x 4 90graph

Two lines in the same plane that do not intersect are called parallel lines. When a line intersects two parallel lines, several pairs of angles that are formed have equal measures.

When two lines intersect to form one right angle, they form four right angles. Two lines that intersect at a right angle are called perpendicular lines.

15x 2 7x 4 90answer

19.  Angles 1 and 2 form a linear pair and are supplementary.  So to find m∠2, subtract m∠1 from 180o.  m∠2 = 180o - 135o = 45o.

Solution The diagram shows that m∠1 = 90. ∠1 and ∠3 are vertical angles. Their measures are equal, so m∠3 = 90. ∠1 and ∠2 are supplementary.

15x 2 7x 4 90calculator

Solution∠1 and ∠5 are corresponding angles, so they have equal measures. Find m∠5. The angle with measure 125 and ∠5 are supplementary.

When two lines intersect at a point, they form two pairs of angles that do not share a side. These pairs are called vertical angles, and they always have the same measure.