What is the value of the function when x = 4?
y = 3x + 7

2x - 3y = 7 and -3x + y = 7..multiply Equation 2 by THREE and add to Equation 1
-9x + 3y = 21watch the y's disappear
-7x = 28
x = -4
substitute -4 instead of x in either of the ORIGINAL equations

2x - 3y = 7
2(-4) - 3y = 7
-8 -3y = 7add 8 to both sides
-3y = 15
y = -5

im not sure

isocolese triangle

we know that the line connect a and b is the hyptonuse

so first find the hypotonuse length using the distance formula, call the length c

since it is an isocolese triangle, the lengths of the legs are the same

using pythagorean theorem,

in this case, a=b since isocolese triangle so we get

or

we can find c so we can find the distances

we know that if we draw 2 circles, each has center at a and b, and find where they intersect, we can the 2 possible locations for c

if a has center at (xa,ya) and b has center at (xb,yb), then we can solve where

and

intersect to find where they intersect

i'm not going to put an example because i have to go to class. i hope this explanation is enough

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