Remark
When you have two parallel lines cutting the sides of a triangle and one of them is the base of the triangle, then the 2 sides cut form a proportion. The safest way to handle this is to set up the proportion so that you are talking about sides of similar triangles..
Givens
BD || AE
CD = 16
CE = 16 + 4
CB = 12
CA = 12 + x
Set Up the Proportion
CD/CE = CB / CA
Substitute and Solve
16/20 = 12/(12 + x) Cross multiply
16*(12 + x) = 20 * 12 Combine the right
16*(12 + x) = 240 Remove the brackets.
192 + 16x = 240 Subtract 192 from both sides.
16x = 240 - 192
16x = 48 Divide by 16
x = 48 / 16
x = 3
Answer:24+4x
Step-by-step explanation:
a=5. PHOTO
b=7. PHOTO
a1=5+x. FRAME
b1=7+x. FRAME
Pf=2*(a1+b1)
Pf=2*(5+x+7+x)
Pf=2*(12+2x)
---------Pf=24+4x. - - - - - - PERIMETER OF FRAME
The constant fraction 1/5 is the coefficient of the variable c in this problem.
20 minutes
2 kilometers equal 2000 meters
100/1= 2000/X
2000=100x
To factor the trinomial, you can use the ac method where you multiply the first and last terms together (6 and 9) and add up to 15.
In this case ac= 54
2 numbers that multiply to 54 and add up to 15 would be 6 and 9 so place these numbers where the 15 would be:

Then group terms to simplify:

Simplify any like terms:

And group together again:

You can simplify a 3 out of the first expression one more time to get:

Which would be the factored form. I hope this helps :)