Below are the 2013 Grade 9 Math Challenge – Elimination Round questions and answers – Part I. More reviewers can be found on the **Past Tests** and **All Posts** pages.

1.) Simplify:

2.) Simplify:

3.) Simplify:

4.) Simplify:

5.) Simplify:

, if x > 0 and y > 0.

6.) Simplify:

7.) Simplify:

8.) Solve: x(6x – 1) = 12

9.) Find the equation of the line with x-intercept 3 and y-intercept -7.

10.) Find the equation of the line passing through (2, 3) and perpendicular to 7x – 5y = 40.

11.) Find the constant *s* so that the lines (2*s* + 4)*x* + 5*y* = -7 and (*s* + 4)*x* + 3*y* = *s* are parallel.

12.) Find the point of intersection of the lines 5*x* + 2*y* = 16 and 10*x* – 3*y* = 46.

13.) Find the supplement of an angle measuring

14.) If and are supplementary, find the complement of

15.) Find *x*.

16.) Find *y*.

17.) Find *RS*.

18.) Find *PQ*.

19.) The four points *A*(-6, 2), *B*(-3, 3), *C*(9, 7) and *D* form Rectangle *ABCD*, what are the coordinates of *D*?

20.) How many circles of radius 9 cm can be cut from a rectanglular sheet 3.7 m by 1.05 m?

21.) In Parallelogram *PARK*, . What is

22.) The angles of a triangle are in the ratio 11 : 12 : 13. Find the measure in degrees of its largest angle.

23.) The vertex angle of an isosceles triangle is 63 degrees. Find the measure of a base angle.

24.) A regular polygon has 15 sides. Find the measure in degrees of each of its interior angles.

25.) An equilateral triangle has perimeter 27 cm. What is its area?

Answer key:

1.)

2.)

3.)

4.)

5.)

6.)

7.)

8.)

9.)

10.)

11.) 8

12.) *x* = 4 and *y* = -2

13.)

14.)

15.) 15

16.) 20

17.) 12

18.) 6

19.) (6, 11)

20.) 100

21.) 30

22.)

23.)

24.)

25.)

View Part II here: 2013 Grade 9 Math Challenge – Elimination Round with answer key – Part II