Without an equality sign the expression given can't be considered to be an equation.
But if you meant: 2y = 18 then y = 9
Any solution to a system of linear equations must satisfy all te equations in that system. Otherwise it is a solution to AN equation but not to the system of equations.
7
Tell me the equations first.
There are people who use this web site that can and will solve equations.
You can use a graph to solve systems of equations by plotting the two equations to see where they intersect
The answer depends on the nature of the equations.
It means that if you replace one variable with one of the numbers, and the other variable with the other numbers, and then evaluate the expressions on each side of the equations, the equalities will be true.
You solve equations with fractions the same way you solve other equations. You perform various arithmetic operations on both sides of the equals sign until you get the result you want.
You need as many equations as you have variables.
One can solve equations of motion by graph by taking readings of the point of interception.
You don't have to. Some people find that it makes subsequent calculations easier - but not all do.
None. Properties of inequalities are not that relevant when solving equalities.