Question

For the system of linear equations below, use graphing to determine in which quadrant the solution lies.
3x+4y=-12
-7x+5y=-35

Quadrant I

Quadrant II

Quadrant III

Quadrant IV

Answer 1

lets eliminate on of the variables.
we multiply the first equation by 7 and the 2nd eqaution by 3
getting

21x + 28y=-84 and
-21x + 15y= -105 add them together
-----------------
43y =-189
y=-4.395 now you know y solve for x

and plot at desmos.com

or just look at the signs of your answers


Quadrant I (+,+)

Quadrant II (-,+)

Quadrant III (-,-)

Quadrant IV (+,-)

Answer 2

is it quadrant 1? @zpupster

Answer 3

no you see the answer for y is negative so by looking at the signs i gave for (x,y) values

the y is negative in which quadrants


also

take the answer we got for y and plug it in and then solve for x

3x+4(-4.395)=-12

Answer 4

quadrant 4? @zpupster

Answer 5

yes

Answer 6

thank you so much! @zpupster

Answer 7

could you help me with this one too? @zpupster

Consider two lines that form a linear system.
Line 1: slope = 2 and y-intercept of (0,-5)
Line 2: slope = 4 and y-intercept of (0,8)

Part 1: What type of lines would this be?
Part 2: How many solutions does this system have?