Triangle ABC is similar to triangle DEF, shown below. Side AB has length 8 and corresponds to side DE of length 40. If side BC has length 7, what is the length of side EF?
A42
B12
C15
D35
Explanation
Similar triangles have proportional sides. Scale factor = DE/AB = 40/8 = 5. So EF = BC × 5 = 7 × 5 = 35.
Question 3 of 10
TEKS GEOEasy Diagram
The triangle shown has a base of 12 and a height of 3. What is its area?
A18
B16
C36
D30
Explanation
Area = ½ × base × height = ½ × 12 × 3 = 18.
Question 4 of 10
TEKS GEOEasy Diagram
The circle shown has a radius of 11. What is the area of the circle, in terms of π?
A121π
B242π
C22π
D11π
Explanation
Area = πr² = π(11)² = 121π. (Don't confuse with circumference 2πr.)
Question 5 of 10
TEKS GEOMedium Diagram
In the right triangle shown, the hypotenuse has length 52 and one leg has length 20. What is the length of the other leg?
A46
B48
C45
D44
Explanation
By the Pythagorean theorem: b² = c² − a² = 52² − 20² = 2704 − 400 = 2304. So b = √2304 = 48.
Question 6 of 10
TEKS ALGMedium Diagram
A line passes through the points (-1, -2) and (1, -6), as shown. What is the slope of the line?