Question

If the two triangles are similar, solve for x

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A. x = 3
B. x = 6
C. x = 9
D. x = 12

Answer 1

the two triangles are similar, so the corresponding sides form a ratio

Answer 2

which means we can say

(x+9)/7 = (x+6)/6

cross multiply to get

6(x+9) = 7(x+6)

then distribute to get

6x + 54 = 7x + 42

I'll let you finish up

Answer 3

what do i do?

Answer 4

from here you just need to isolate x

Answer 5

6x + 54 = 7x + 42

6x + 54 - 54 = 7x + 42 - 54

6x = 7x - 12

...
...
...

x = ???

Answer 6

i dont know how to finish that :/

Answer 7

are you familiar with solving linear equations?

Answer 8

not really no

Answer 9

alright, what you want to do is move the 7x over

so you need to undo adding 7x

so you do what?

Answer 10

i learned them but never quite got them

Answer 11

how do we undo +7x

Answer 12

make it negative?

Answer 13

close, you subtract 7x from both sides

Answer 14

6x - 7x = 7x - 12 - 7x

notice how the 7x - 7x on the right side will become 0x or just 0

Answer 15

so now its 6x - 12 ?

Answer 16

what is 6x - 7x simplify to

Answer 17

1x? or -1x? im really bad at math

Answer 18

6x - 7x is -1x

Answer 19

so we now have

-1x = -12

Answer 20

if

-1x = -12

then

x = ??