18. Which ordered pair is a solution of the system of linear equations listed below? 2x + y = -5
-x+3y=6
A. (-3, 1)
B. (3, 1)
C. (-3,-1)
D. (-1,3)​

A

Step-by-step explanation:

Given the 2 equations

2x + y = - 5 → (1)

- x + 3y = 6 → (2)

Multiplying (2) by 2 and adding to (1) will eliminate the x- term

- 2x + 6y = 12 → (3)

Add (1) and (3) term by term to eliminate x

0 + 7y = 7

7y = 7 ( divide both sides by 7 )

y = 1

Substitute y = 1 into either of the 2 equations and solve for x

Substituting into (1)

2x + 1 = - 5 ( subtract 1 from both sides )

2x = - 6 ( divide both sides by 2 )

x = - 3

solution is (- 3, 1 ) → A

answer

a,b, and d

explanation

a reflection angle is more than

but less than;

an angle that measures

is a reflex angle.(true)

an angle that measures less than

is acute.(true)

provided we are considering angles greater or equal to zero.

an acute angle lies in the range.

an obtuse angle is less than 180° but more than 90°

an angle that measures 300° is obtuse (false)

an angle that measures 65° is an acute angle.(true)