Question

I need help with number 3

Answer 1

AB=54

Explanation:

in Δs ABD and ACD

BD=CD (given)

∠ADB=∠ADC (each right angle)

AD=AD (common)

∴ ΔABD≅ΔACD

so AB=AC

4x+6=5x-6

6+6=5x-4x

x=12

AB=4×12+6=48+6=54

Answer 2

AB = 54

Explanation:

AB = AC

4x+6 = 5x-6

Subtract 4x from each side

4x+6-4x = 5x-6-4x

6 = x-6

Add 6 to each side

6+6 =x

12 =x

We want to find AB

AB =4x+6

4(12)+6

48+6

54