Solve elimination 5x+y=9 10x-7y=-18
1 answer:
<h2>(1, 4)</h2><h2 />
To solve this system by addition, notice that if we add these two equations together, neither one of our variables will cancel out.
In this situation, we need to set things up so that when we do add our two equations together, one of the variables will cancel out.
Notice that we have a 10x in our second equation. if we had a -10x in our first equation, then the x's would cancel out.
To create a -10x, we can multiply the top equation by -2 to get a -10x.
From there, rewriting our equation gives us -10x - 2y = -18.
Now the x's cancel. Just add the equations together
now to get the two-step equation -9y = -36.
Solving from here, <em>y = 4</em>.
Now plug y into either one of the equations
to find that x =1.
So our solution is (1,4).
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If you wanted to simplify that it would be
Answer:
- value: $66,184.15
- interest: $6,184.15
Step-by-step explanation:
The future value can be computed using the formula for an annuity due. It can also be found using any of a variety of calculators, apps, or spreadsheets.
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<h3>formula</h3>The formula for the value of an annuity due with payment P, interest rate r, compounded n times per year for t years is ...
FV = P(1 +r/n)((1 +r/n)^(nt) -1)/(r/n)
FV = 5000(1 +0.06/4)((1 +0.06/4)^(4·3) -1)/(0.06/4) ≈ 66,184.148
FV ≈ 66,184.15
<h3>calculator</h3>The attached calculator screenshot shows the same result. The calculator needs to have the begin/end flag set to "begin" for the annuity due calculation.
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<h3>a) </h3>The future value of the annuity due is $66,184.15.
<h3>b)</h3>The total interest earned is the difference between the total of deposits and the future value:
$66,184.15 -(12)(5000) = 6,184.15
A total of $6,184.15 in interest was earned by the annuity.
