Question

8x+5y=-13 3x+4y=10 solve

Answer 1

Answer:

x=−6 and y=7

Step-by-step explanation:

Step: Solve8x+5y=−13for x:

8x+5y=−13

8x+5y+−5y=−13+−5y(Add -5y to both sides)

8x=−5y−13

8x

8

=

−5y−13

8

(Divide both sides by 8)

x=

−5

8

y+

−13

8

Step: Substitute

−5

8

y+

−13

8

forxin3x+4y=10:

3x+4y=10

3(

−5

8

y+

−13

8

)+4y=10

17

8

y+

−39

8

=10(Simplify both sides of the equation)

17

8

y+

−39

8

+

39

8

=10+

39

8

(Add 39/8 to both sides)

17

8

y=

119

8

17

8

y

17

8

=

119

8

17

8

(Divide both sides by 17/8)

y=7

Step: Substitute7foryinx=

−5

8

y+

−13

8

:

x=

−5

8

y+

−13

8

x=

−5

8

(7)+

−13

8

x=−6(Simplify both sides of the equation)Step: Solve8x+5y=−13for x:

8x+5y=−13

8x+5y+−5y=−13+−5y(Add -5y to both sides)

8x=−5y−13

8x

8

=

−5y−13

8

(Divide both sides by 8)

x=

−5

8

y+

−13

8

Step: Substitute

−5

8

y+

−13

8

forxin3x+4y=10:

3x+4y=10

3(

−5

8

y+

−13

8

)+4y=10

17

8

y+

−39

8

=10(Simplify both sides of the equation)

17

8

y+

−39

8

+

39

8

=10+

39

8

(Add 39/8 to both sides)

17

8

y=

119

8

17

8

y

17

8

=

119

8

17

8

(Divide both sides by 17/8)

y=7

Step: Substitute7foryinx=

−5

8

y+

−13

8

:

x=

−5

8

y+

−13

8

x=

−5

8

(7)+

−13

8

x=−6(Simplify both sides of the equation)

Answer 2

Answer: The intersection between these 2 lines are (-6,7)

Source: Desmos Graphing Calculator (look it up its very helpful and gives answers)