add 4 to each side: c + 7 = d so d is greater than c by 7.
12
That's the equation.
It equals to the equation of a straight line.
y=3
It is an equation and the value of b is 3
12
That's the equation.
an equation 3 + 3 = 6
4
21
no not really
It equals to the equation of a straight line.
x = 3
y=3
It is an equation and the value of b is 3
Without an indication of the equals sign, this is not an equation.
Yes.