. HELP ME PLEASE

Use only mathematical concepts, prove the following a valid formula.
O = *square root of O squared*
Be sure to use the method of L. H.S. and R. H.S. to ensure you get full marks.
Why do we need to calculate standard deviation if it is simply the square root of the
variance?

step-by-step explanation:

y = | -2(-2) |     →     y = | 4 |     →     y = 4       ⇒   (-2, 4)

y = | -2(-1) |     →     y = | 2 |     →       y =   2       ⇒   (-1, 2)    

y = | -2(0) |     →     y = | 0 |     →       y = 0         ⇒   (0, 0)

y = | -2(1) |   c →     y = | -2 |     →     y =   2         ⇒   (1, 2)    

y = | -2(2) |     →     y = | - 4 |     →     y =   4         ⇒   (2, 4)  

the answer will be b x² +x-1

step-by-step explanation:

answer: x=3 and y=4

step-by-step explanation: