Answer:
Step-by-step explanation:
the solution is right
x^2-6x-7=0:
x^2-6x-7=0
(add 7 to both sides)
x^2-6x=7
x^2-6x+9=7+9 (the coefficient of x² will be used to divide all sides)for here its 1, it will remain same ,
then we get the coefficient of x, divide it by 2 and square it and add it to both sides
which is like these
x²-6x=7
the coefficient of x is -6
-6/2 = -3, square it (-3)² = 9
then add 9 to both sides
x^2-6x+9=7+9
simplifiy the squares on the left hand side
x²+9 = (x-3)²
(x-3)^2=16
√(x-3)^2 )=±√16
x-3=± 4
x=-3±4
then simplify each sign
x=-3+4 x=-3-4
x=1 x=-7
Answer:
f(4) = -4
Step-by-step explanation:
f(x) = 4x - 20
Let x= 4
f(4) = 4*4 - 20
Multiply first
= 16 -20
Then subtract
= -4
Answer:
15
Step-by-step explanation:
4 (Book per cost)+ 4.47 (Shipping Fee) = 8.75 cost of one book $132.75 Divided by $8.75 = 15 Books bought.
Not sure i remember this but i think radius is like half of the diameter. it’s a line from the center, to a side of the circle. in this situation, line RO would be representing the radius.
answer: D, line RO
hope this helps :)
Answer:
0.0323 = 3.23%. Is unusual
Step-by-step explanation:
Using the normal distribution we can find z value with the mean and standard deviation as follows. x is the value we want to know its probability
z = (x - mean)/standard deviation
z = (5-8.54)/1.91
z = -1.85
Using z tables for normal distribution, for z = 1.85, we have an area under the curve of 0.9677. Since we want to know the probability for 5 minutes or less, we have to substract from
p = 1- 0.9677
p = 0.0323
An event with a probability less than 5% is considered unusual.
