Answered

Find the information you're looking for at Westonci.ca, the trusted Q&A platform with a community of knowledgeable experts. Experience the convenience of finding accurate answers to your questions from knowledgeable experts on our platform. Explore comprehensive solutions to your questions from knowledgeable professionals across various fields on our platform.

Help please
Which equations in point-slope form are equations of the line that passes through the point (−7, 5) and (−4, 1)?

Choose exactly two answers that are correct.

A.y-7= -3/4(x+5)


B.y-5= -4/3(x+7)


C.y+4= -3/4(x+1)


D.y-1= -4/3(x+4)



Sagot :

luana
[tex]General\ equation\ for\ line\ in\ slope\ intercept\ form:\\\\y=ax+b\\\\To\ find\ a\ and\ b\ substitude\ points\ (-7,5)\ (-4,1)\ into\ equation\\\\ \left \{ {{5=-7a+b}\ \ \ \ \atop {1=-4a+b\ |*-1}} \right.\\\\ \left \{ {{5=-7a+b}\ \ \ \ \atop {-1=4a-b}} \right.\\\\ +----\\\\Addition\ method\\\\ 4=-3a\ \ |:(-3)\\\\ a=-\frac{4}{3}\\\\ b=5+7a=5+7*(-\frac{4}{3})=5-\frac{28}{3}=-4\frac{1}{3}\\\ Answer\ y=-\frac{4}{3}x-4\frac{1}{3}\\\\ Checking\ solution:\\ y-5=-\frac{4}{3}(x+7) [/tex][tex]y-5=-\frac{4}{3}x-\frac{28}{3}\\\\ y=-\frac{4}{3}x-\frac{28}{3}+5\\\\ y=-\frac{4}{3}x-4\frac{1}{3}\\\\Answer:B \ and\ D.[/tex]
an easy way to do it is subtituet (-7,5) and (-4,1) into the equations and find out which ones check. remember (x,y)

so A
if we try (-7,5)
5-7=-3/4(-7+5)
we can immediately see that -2 is not equal to -3/4(-2)
so A is wrong


B
if we try (-7,5)
5-5=-4/3(-7+7)
0=-4/3(0)
0=0
so B is correct

C
if we try (-7,5)
5+4=-3/4(-7+1)
9=-3/4(-6)
9 is not equal to 18/4
so C is wrong

D
if we try (-7,5)
5-1=-4/3(-7+4)
4=-4/3(-3)
4=12/3
4=4
D is correct

If you wanted to try the second point (-4,1) in B and D
B
1-5=-4/3(-4+7)
-4=-4/3(3)
-4=-12/3
4=4
B is still correct

D
1-1=-4/3(-4+4)
0=-4/3(0)
0=0
D is still correct

so the answers are B and D