Answer:
4
Step-by-step explanation:
2+2 = 4
1+1 = 2 x 2 = 4
Got it
1. .35(15) + .72(5) = 8.85
2.8.85/(15 + 5) = 0.4425 = 44.25%Answer:
Step-by-step explanation:
Answer:
B
Step-by-step explanation:
x + 3y = 7 → (1)
3x + 2y = 0 → (2)
Multiplying (1) by - 3 and adding to (2) will eliminate x
- 3x - 9y = - 21 → (3)
Add (2) and (3) term by term to eliminate x
0 - 7y = - 21
- 7y = - 21 ( divide both sides by - 7 )
y = 3
Substitute y = 3 into either of the 2 equations and solve for x
Substituting into (1)
x + 3(3) = 7
x + 9 = 7 ( subtract 9 from both sides )
x = - 2
solution is (- 2, 3 ) → B
Answer:
Step-by-step explanation:
I used Cramer's Rule to find y, since we can isolate and solve for individual variables using Cramer's Rule. Do that by finding the determinant of the matrix, |A|. The matrix A looks like this:
2 -2 1
-1 3 2
1 -4 -3
and we find the determinant of a 3x3 by expanding it. Do that by picking up the first 2 columns and throw them on at the end, like this:
2 -2 1 2 -2
-1 3 2 -1 3
1 -4 -3 1 -4
and find the determinant by multiplying along the 3 major axes and subtract from that the product of the 3 minor axes:
[(2*3*-3)+(-2*2*1)+(1*-1*-4)] - [(1*3*1)+(-4*2*2)+(-3*-1*-2)] which simplifies to
-18 - (-19) = 1
So the determinant of the matrix A is |A| = 1.
Now to find the determinant of Ay, we replace the y column with the solutions and so the same thing by expansion and then multiplying and subtracting:
2 -7 1 2 -7
-1 0 2 -1 0
1 1 -3 1 1
and find the determinant of y:
[(2*0*-3)+(-7*2*1)+(1*-1*1)] - [(1*0*1)+(1*2*2)+(-3*-1*-7)] which simplifies to
-15 - (-17) = 2
So the detminant of y is |Ay| = 2
We can solve for the variable now by dividing Ay by A:
2 / 1 = 2
So the solution for y = 2
The correct answer is B.
In order to prove which of the function rules provided is the one corresponding to the schedule represented by the table, the different y-values need to be sustituted in the function rules. <u>Only the correct function rule will yield the corresponding x-value. </u>
<u>Let's prove that option B is the correct one</u>
FUNCTION B y= 5x - 14
- If x= -4 --> substituting: 5(-4) - 14= -20 - 14= -34 therefore, y= -34 <u>CORRECT</u>
- If x= -1 --> 5(-1)-14 = -5 - 14= -19 therefore y= -19 <u>CORRECT</u>
- If x= 2 --> 5(2) - 14= 10-14= -4, therefore y= -4 C<u>ORRECT</u>
- If x= 4 --> 5(4)-14= 20-14= 6, therefore y=6<u> CORRECT</u>
- If x= 7 --> 5(7) -14= 35-14= 21, therefore y=21 <u>CORRECT</u>
