In triangel abc line segmemt cd is an altitude, such that ad=bc. find ac if ab=3cm and cd =sqrt2

√7

Step-by-step explanation:

Let :

AC = x

BD = y ; AD = 3 - y

Since, AD = BC

Then BC = 3 - y

Taking △BDC a d applying Pythagoras

Hypotenus² = opposite² + adjacent²

BC² = CD² + BD²

(3 - y)² = (√3)² + y²

9 - 6y + y² = 3 + y²

-6y + y² - y² = 3 - 9

-6y = - 6

y = 1

AD = 3 - y ; AD = 3 - 1 = 2

Taking △ADC

AC² = CD² + AD²

AC² = (√3)² + 2²

AC² = 3 + 4

AC² = 7

AC = √7

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.