Need to know how to do it aswell. doing Similar Triangles unit

x = 14

Step-by-step explanation:

Similar triangles have the property that the measure of its corresponding sides is proportional.

This can be written as:

Cross-multiplying the fractions:

Operating:

Factoring:

(x-14)(x+10)=0

Solving:

x=14, x=-10

Only positive values can be accepted for x, thus:

x = 14

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -