Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar. is parallel to , and is perpendicular to . The number of 90° angles formed by the intersections of and the two parallel lines and is .

The question is not complete, below is a complete question with the accompanying diagram:

Instructions: Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar.

AB is parallel to CD, and EF is perpendicular to AB

The number of 90° angles formed by the intersections of Ef and the two parallel lines AB and CD is ____

The number of 90° angle formed = 8 angles

Step-by-step explanation:

From the question and attached diagram, the following information is given:

AB is parallel to CD

EF is perpendicular to AB

Required: number of 90° angles formed by the intersection of the perpendicular line and the parallel lines.

Note, the angle formed between a line and a perpendicular line = 90°

From the diagram:

Number of 90° angle formed by intersection of perpendicular line EF and line AB = ∠1, ∠2, ∠3 and ∠4 = 4 angles

Number of 90° angle formed by intersection of perpendicular line EF and line  CD = ∠5, ∠6, ∠7 and ∠8 = 4 angles

Total 90° angles formed by perpendicular line with lines = ∠1, ∠2, ∠3, ∠4, ∠5, ∠6, ∠7, and ∠8 = 8 angles

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240

-9

step-by-step explanation: