92.0k views
3 votes
Solve the Systems of equations algebraically

4x+5y=15
-4x+6y+7

Answers
A- (5/4, 2)
B- (2, 5/4)
C- (4/5,2)
D (2, 4/5)

2 Answers

7 votes

Answer:

5/4, 2 or A on edge 2021

Explanation:

took the test :)

User David Weldon
by
6.5k points
2 votes
STEP 1:
4x + 5y= 15
-4x + 6y= 7
add the two above equations; the x term cancels out; solve for y

11y= 22
divide both sides by 11

y= 2


STEP 2:
substitute the y value in step 1 into either original equation

4x + 5y= 15
4x + 5(2)= 15

4x + 10= 15
subtract 10 from both sides

4x= 5
divide both sides by 4

x= 5/4


ANSWER: (A) x= 5/4, y= 2 or (5/4, 2)

Hope this helps! :)
User Binary Pulsar
by
5.1k points