(x + a) (x + b) = x² + (a + b) x + ab
75 * 77=
=(70+5)(70+7)
=70²+(5+7)*70+5*7
=4900+12*70+35
=4900+840+35
=5775
Answer:
A
Step-by-step explanation:
1/2x-4=-2x-9...u vil get the ans
You don't solve a quadratic equation using completing the square
Let's put it this way.
It's a ratio of 6:72 and we need to change it in a way to find number of rooms cleaned in 9 days.
Divide 6 & 72 both by 2
Ratio is now 3:36
Multiply 3 & 36 both by 3
Ratio is now 9:108
The number of rooms in which Robin can clean in 9 days is 108 rooms.
