Question

if a,b,c and d are in proportion then prove that. (5a + 7b)(2c - 3d) = (5c + 7d)(2a - 3b)

Answer 1

Answer:

proved

Step-by-step explanation:

a,b,c,d are in proportion

⇒ad=bc

Now

LHS:  

(5a+7b)(2c−3d)

=10ac−15ad+14bc−21bd

=10ac−21bd−ad

RHS

(5c+7d)(2a−3b)

=10ac−15bc+14ad−21bd

=10ac−21bd−ad

⇒LHS=RHS