C. 25
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Divide 400/100=4
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Than divide 4/100
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Yes, for every value of x, there is only one value of y. This means that y is a function of x.
After one hour, the plane is 225 miles from its destination
[x-1]=5x+10
We have two equations:
1) x-1=5x+10
x-1=5x+10
x-5x=10+1
-4x=11
x=-11/4
2) x-1=-(5x+10)
x-1=-(5x+10)
x-1=-5x-10
x+5x=-10+1
6x=-9
x=-9/6=-3/2
we have two possible solutions:
solution₁; x=-11/4
solution₂: x=-3/2
we check it out:
1) x=-11/4
[x-1]=5x+10
[-11/4 - 1]=5(-11/4)+10
[(-11-4)/4]=-55/4 + 10
[-15/4]=(-55+40) /4
15/4≠-15/4 This solution don´t work.
2) x=-3/2
[x-1]=5x+10
[-3/2 - 1]=5(-3/2)+10
[(-3-2)/2]=-15/2 + 10
[-5/2]=(-15+20)/2
5/2=5/2; this solution works.
Therefore:
Answer: x=-3/2.
The solution to given system of equations are (x, y) = (4, 2)
<em><u>Solution:</u></em>
<em><u>Given system of equations are:</u></em>
2x + 3y = 14 ---------- eqn 1
3x - 4y = 4 --------- eqn 2
We have to solve the given system of equations
We can solve the above system of equations by elimination method
<em><u>Multiply eqn 1 by 3</u></em>
3(2x + 3y = 14)
6x + 9y = 42 --------- eqn 3
<em><u>Multiply eqn 2 by 2</u></em>
2(3x - 4y = 4)
6x - 8y = 8 ----------- eqn 4
<em><u>Subtract eqn 4 from eqn 3</u></em>
6x + 9y = 42
6x - 8y = 8
( - ) --------------
9y + 8y = 42 - 8
17y = 34
<h3>y = 2</h3>
<em><u>Substitute y = 2 in eqn 1</u></em>
2x + 3(2) = 14
2x + 6 = 14
2x = 14 - 6
2x = 8
<h3>x = 4</h3>
Thus the solution to given system of equations are (x, y) = (4, 2)