Question

Given: angle 1 = angle 2

If AC = 3, BC = 5, and AB = 7, find AD:


A. 2 5/8

B. 4 1/5

C. 4 3/8

D. 11 2/3

Answer 1

what is 1 and 2?

Answer 2

angle 1= angle 2.

Answer 3

hotty

Answer 4

can you see two similar triangles?

Answer 5

AC/AD = BD/BC
AD+BD=AB

Answer 6

@Diana691 can you solve now?

Answer 7

okay but AD and BD are unknown.

Answer 8

Yes we have two variables and two equation

Answer 9

AD+DB= AB

Answer 10

can you show me step by step. please

Answer 11

assume AD =x then DB = 7-x solve the quadratic equation

Answer 12

let us do it together here. if you are stuck I will help you!

Answer 13

@Diana691 put the values in second equation and form the equation

Answer 14

okay -x squared =7x?

Answer 15

3*5 = x*(7-x)

Answer 16

3x=35-5

Answer 17

NOoooo

Answer 18

what am i doing wrong? ;/

Answer 19

can you make equation from this 3*5 = x*(7-x)
* means multiply.

Answer 20

x squared -7x+15

Answer 21

can you help me @GuttierreOliveira

Answer 22

@nikato

Answer 23

Try finding the angles.

Answer 24

If u still need help, can u tell me if there is any more given info like if any r right angles

Answer 25

Hi @Diana691 , do not know if you've managed to make the exercise more here's my explanation lol
this is basically the same thing as the others !
when he says that the angle 1 = angle 2 means that the legs assumed the same values ​​and the same proportion (not sure if this definition is correct , but I think it is ) . eg
if the triangle which has 1 angle is 30 ° and a hypotenuse with value 3, where the line AC , you can find the AD line using the law of sin !
Now if you performed the same operation on the triangle that takes the angle 2 has already been defined (if angle 1 = angle 2 then angle 2 = 30 ° ) using the same values ​​above , you agree that the result would be the same ? However , if we change the value of a leg will change the result , but in the same proportion :) and change the angle values ​​also changed , (because sin 30 ° = 0.50 and sin 60 ° = 0.8660 ... . )
As we do not have the value of the angle, we must do what we had already done !
AC = 3
BC = 5
AB = 7 - AD
AD = x

AC/BC = AD/AB
3/5 = x/7 - x  ( AD = X then I replace here)
5x = 21 - 3x
8x = 21
x = 21 / 8 or 2,62...

I do not quite understand the answers but I think "A" is because
5/8 = 0.625
be added + 2 = 2,625
more if it is 25/8 . I do not know how to do ! :)