Answer:
When x1 and x2 decrease 4 units, y decreases by 20 units
Step-by-step explanation:
The regression model is
We have to calculate y for a decrease of 4 units in x1 and x2. For this we have to calculate the variation of y in function of x1 and x2.
As it is a linear regression model, we have:
For a variation in 4 units of x1 and x2, we have
12. 1500 cm²
13. Monica forgot to multiply by 1/2
The area of the fabric is 45 in²
Hope this helped!! (:
Check whether the two expressions 2x+3y2x+3y and 2y+3x2y+3x equivalent.
The first expression is the sum of 2x2x 's and 3y3y 's whereas the second one is the sum of 3x3x 's and 2y2y 's.
Let us evaluate the expressions for some values of xx and yy . Take x=0x=0 and y=1y=1 .
2(0)+3(1)=0+3=32(1)+3(0)=2+0=22(0)+3(1)=0+3=32(1)+3(0)=2+0=2
So, there is at least one pair of values of the variables for which the two expressions are not the same.
The equation is
.
We are looking for a function with a vertex above the x-axis and a function that opens upward (has coefficient a > 0).
The first function opens downward and intersects the x-axis. The second function has a vertex below the x-axis. The third function satisfies our requirements. The fourth function has a vertex on the x-axis.
We can solve this algebraically with the knowledge that the real solutions of a quadratic are its x-intercepts. If there are no x-intercepts (because it lies entirely above or below the x-axis), then there are no real solutions. This is true when the discriminant
. You can see that from the quadratic formula. This holds true for both answers A and C, so to find the correct one, we remember that when the coefficient a of the
term is positive, the graph opens upwards, so we choose
C.
