The largest triangle and the triangle whose hypotenuse is x are similar. So:
(21 + 4)/x = x/4
Cross multiply:
x^2 = 100
x = 10
Your answer is incorrect. It should be 10, not 20.
The required algebraic expression will be "
". A complete solution is provided below.
According to the given question,
- Let the number be "x".
- Five less than this number will be "x-5"
Now,
The product of the lesser number with 7 will be:
=
...(Algebraic expression)
By solving this, we get
= 
Thus the above answer is appropriate.
Learn more about algebraic expression:
brainly.com/question/24021199