whenever a number has a negative sign,the larger the number the smaller.
i.e (-55/10= -5.5) is smaller than -32/40=-0.8 and then the greatest is 5 since it is a positive number and positive numbers are greater than negative numbers.
when a rotation of 180 ° happens, it switches the (x,y) coordinates from (x,y) to (-x,-y) .. that's alll... soo for M then, of (3,4) it switches to M ' = ( -3, -4) see?
