Multiply the first equation by -1
-3x-y=-4
2x+y=5
Add them up
-x=1
So x=-1
And y=7
So the first option is correct
To calculate the tax multiply $860 by .06 (6%) to get $34.40.
To calculate the total amount you'll pay add $34.40 to $860 to get $894.40.
<span>3 of the 20 toothbrushes are defective, so the initial probability of selecting a defective toothbrush on the first try is 3/20. After that, there will be 2 defective toothbrushes in the remaining 19, so the probability of selecting one of those on the 2nd try will be 2/19. To get the probability of those two events happening sequentially, we multiply the two probabilities. Thus (3/20)*(2/19) = 6/380 = 0.0157, or about 1.6%.</span>
Based on the above scenario, the sales director conducted an <u>experiment</u>.
- Because a treatment <u>was </u>applied to the sales representatives.
- The the best statistical study for this situation because the sales director is trying to establish <u>correlation</u>.
<h3>What is an experiment?</h3>
An experiment is known to be a method that is et up with the aim to test a given hypothesis as a component of a scientific method.
In an experiment, there are the two key variables which are the independent and dependent variables. The independent variable is known to be a controlled or it is tested against the dependent variable.
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Part A.
The sales director conducted a.) an experiment b.) a survey c.)an observational study because a treatment a.) was not b.)was applied to the sales representatives.
This is the best statistical study for this situation because the sales director is trying to establish a.) causality b.) correlation.
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<h3>Given Equation:</h3>
x = 7 + 3y
or, x - 3y - 7 = 0 ........ (i)
5x + 6y = 14
or, 5x + 6y - 14 = 0 .........(ii)
<h3>To Find:</h3>
The value of x and y.
<h3>Solution:</h3>
By dividing eq. ii by 2, we get
5/2x + 3y - 7 = 0 ........ (iii)
By adding eq. i and eq. iii, we get
15/2x = 0
or, <u>x = 0</u> ........(iv)
By putting eq.(iv) in eq. (i), we get
0 - 3y - 7 = 0
or, -3y = 7
or, <u>y = </u><u>-</u><u>7/</u><u>3</u>
<h2>Answer: ( 0, -7/3 )</h2>
The value of x and y is 0 and -7/3 respectively.