1: 8a-3=2a+4
2: (-31)×[(-2)+(-8)] = [(-31)×(-2)]+[(-31)×(-8)
3: If x is a root of the equation 4x=12 then find the value of 3x-9
4: Find the value of 9b-2(3b-2)=16
Answers
8a-3a=4+3=5a=7,a=7/5=2.4
Answer:
Step-by-step explanation:1: taking constant on one side of the equal to sign and variables on the other side ,weget;
8a-2a=4+3
Operator (+,-,×,/) of the terms becomes on moving from LHS to RHS and vice-versa
6a=7
a=7/6
2: (-31) × [(-2) + (-8)] =[(-31) × (-2)] + [ (-31) ×(-8)]
In the question above,we have to verify distributive property over addition.So, first we have to solve LHS and then solve RHS
LHS
(-31) ×[(-2)+(-8)]= (-31)×[-2-8]
= (-31) × [-10]
= -31×-10=310.
RHS
[(-31)×(-2)] + [ (-31) ×(-8)]
=[62] +[248]
=62+248=310.
Hence,LHS=RHS
3: Since, x is the root of equation
4x=12
By transposing method,we have
X=12/4=3
Now , we have to find 3x-9
So,putting x=3
(3×3)-9=9-9=0.
4: 9b -2 ( 3b -2)= 16
According to BODMAS,solving the paranthesis first,
9b-(6b + 4)=16
Opening the paranthesis
9b -6b - 4 = 16
Taking constant on one side and variables on other side of equal to sign
9b - 6b = 16 + 4
2b = 20
b = 20/2 =10.