Answer:

Step-by-step explanation:
The calculator approximated the value of y at 7.8.
We need to complete the error interval for y.
In other words, we calculate the upper and lower bound for y.
The level level of accuracy is to the nearest tenth.
To find the lower bound, we subtract half the degree of accuracy to get:

To find the upper bound, add half the level of accuracy to get:

Therefore the error interval is

Answer:
y hat = 2114.20 + 18.96x
Step-by-step explanation:
Given the least square regression model equation:
y hat = -959.00 + 8.60x
weld diameter x ; shear strength y (in pounds)
1 lb = 0.4536 kg
To express shear strength y in kilogram:
y is multiplied by 0.4536
(y hat × 0.4536) = -959.00 + 8.60x
Divide both sides by 0.4536
(y hat × 0.4536) / 0.4536= (-959.00 + 8.60x) / 0.4536
y hat = 2114.1975 + 18.959435x
y hat = 2114.20 + 18.96x
Answer:
B
Step-by-step explanation:
Just did it.
Answer:
Lesser x = -9
Greater x = 9
Step-by-step explanation:
Step-by-step explanation:
they're is a neat little trick.
but first of all, "roots" means the 0 solutions of the equation. like
ax² + bx + c = 0
there are 2 solutions for x to make the whole expression equal 0.
these are the "roots".
now to the little trick :
when is a multiplication resulting in 0 ?
when at least one of the factors is 0.
and any quadratic expression can be written as multiplication of 2 factors. like
c(x - a)(x - b) = cx² - cax - cbx + cab
what are the "roots" or 0 points ?
either
c = 0
x - a = 0 | x = a
x - b = 0 | x = b
the leading coefficient = 3.
that means nothing else than c = 3.
root = 1 means (x - 1) is one factor.
root = -5 means (x + 5) is the other factor.
so, we have
3(x - 1)(x + 5) = 3x² + 12x - 15
and the equation is
3x² + 12x - 15 = 0
or
3x² + 12x = 15