Question

1. a triangle with one angle of 90° is called: *

a. equilateral
b. isosceles
c. right - angled
d. scalene

1. a quadrilateral with all sides equal and all angles 90° is called: *

a. square
b. rectangle
c. rhombus
d. parallelogram

Explanation:

1. By definition, a triangle with one 90 - degree angle is a right - angled triangle.
2. A square is a quadrilateral with all sides equal and all angles equal to 90 degrees.

Answer:

1. C. Right - angled
2. A. Square