SAT Question:

In a parallelogram. What is the value of c-b

/[3a-15] --------- [b]/
| |
| |
/[2a-5)----------- [c]/

The answer is 30 but I don't know how to do it.
I know that 2a-5 is equal to b and 3a-15 is equal to c.
I know the total degree is 360.

All I have is 76=a+b+c

Question

SAT Question:

In a parallelogram. What is the value of c-b

/[3a-15] --------- [b]/
|                                   |
|                                   |
/[2a-5)----------- [c]/

The answer is 30 but I don't know how to do it.
I know that 2a-5 is equal to b and 3a-15 is equal to c.
I know the total degree is 360.

All I have is 76=a+b+c

ikram002p · Answer

graph ?

anonymous · Answer

/[3a-15] --------- [b]/
|                                   |
|                                   |
/[2a-5)----------- [c]/

Not too scale from the diagram.

anonymous · Answer

to*

anonymous · Answer

opposite angle = 180 degrees
 3a-15 +c = 2a-5 +b
c-b= -a +10

hartnn · Answer

actually opposite angles are congruent
and adjacent angles sum upto 180

anonymous · Answer

oh yes xD  , but same form? :o

ikram002p · Answer

first find a 
since 3a-15+2a-5=180

hartnn · Answer

3a-15= c
2a-5 =b

b+c=180

3 equations
3 unknowns

ikram002p · Answer

mmm :o

ikram002p · Answer

mmm i rather that he/she find z first xD
so it would be simple system

hartnn · Answer

add these
3a-15= c
2a-5 =b

and use 3rd equation b+c =180
and you will be able to find a

midhun.madhu1987 · Answer

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