Question

a*b=8
a*c=21
b-d=5
c*d=9
Find a b c and d

Answer 1

Answer:

A+D=8 →eqn1

B-D=5→eqn2

A×C=21 eqn3

C×D=9 eqn4

eqn3+4

C(A+D)=30, eqn5

eqn 1–eqn2,

A+D=3, put in eqn5

we get,C×3=30, C=30/3=10,

eqn3 –eqn4

C(A-D) =12 , put C=10, then A-D=12/10=1.2

eqn1 + eqn2

A-D+2B=13, put A-D=1.2, then, 2B=13–1.2=11.8

B=11.8/2=5.9

Put the value of C in eqn3&4,

we get, A×10=21, A=21/10=2.1, &10×D=9, D=9/10=0.9,

Hence, A=2.1, B=5.9, C=10&D=0.9

Answer 2

Step-by-step explanation:

a=8/b

a=21/c

8/b=21/c

8c=21b

c=21b/8.