please answer this question
Answers
Solution :-
Given equation is 4x-3 = 2x+1
=> 4x-2x = 1+3
(Transposed 2x then it becomes -2x and transposed -3 then it becomes +3)
=> 2x = 4
=> x = 4/2
=> x = 2
The value of x = 2
The solution = 2
Check :-
LHS = 4x-3
=> 4(2)-3
=> 8-3
=> 3
RHS = 2x+1
=> 2(2)+1
=> 4+1
=> 5
LHS = RHS is true for x = 2
(a)
Expression :-
The combination of a variable and a constant with the operations + or - is called an expression.
Ex : ax+b , 6x-5 , 8x+7 etc.
Equation :-
Two expressions with equality sign is called an Equation.
Ex: ax+b = 0 , ax = b ,ax²+bx+c = 0, ax³+bx²+cx+d = 0 9x+7 = 9 etc.
Linear equation:-
An equation of order 1 is called A linear equation.
- ax+b is an expression and ax+b = 0 is an equation.
- The equality of two expressions is an equation
- In an equation LHS = RHS
- An expression contains atleast one variable is an algebraic expression.
(b)
i) Let the number be X
Half of the number = X/2
According to the given problem
(X/2)+2 = 18
=> (X+4)/2 = 18
=> X+4 = 2×18
=> X+4 = 36
=> X+4-36 = 0
=> X-32 = 0
ii)Let the age of Mohan's sister be X years
The age of Mohan = X+15 years
Sum of their ages = 30
=> X+(X+15) = 30
=> X+X+15 = 30
=> 2X+15 = 30
=> 2X+15-30 = 0
=> 2X-15 = 0