A math student has a plan to solve the following system by the elimination method. To eliminate the x-terms, he wants to multiply the top equation by 7. What should he multiply the second equation by so that when he adds the equations, the x-terms are eliminated?
-3x-7--56
-7x+10y - 1

-3

Step-by-step explanation:

7(-3x-7y-56)

-21x-49y-392

-3(-7x+10y-1)

21x-30y+3

because the eq. multiplied by 7 is negative, the second eq mus be positive in order to eliminate the x variable. this is why we multiply by a (-). by multiplying the second eq by 3, both eq. will result in a coefficient of 21. one positive one negative allowing the x variable to be eliminated from the problem.

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

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