Answer:
$3800
Step-by-step explanation:
When simple interest is added to the principal amount, the sum increases linearly with time. Essentially, you are asked for the y-intercept of a line that goes through the points (2, 6200) and (3, 7400). You can use the 2-point form of the equation of a line to find it:
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
y = (7400 -6200)/(3 -2)(x -2) +6200 . . . . fill in given points
y = 1200(x -2) +6200 . . . . . . . . . simplify some
y = 1200x -2400 +6200 . . . . . . simplify more
y = 1200x +3800 . . . . . . . . . . . . . completely simplify
When the number of years (x) is zero, the amount is 3800. The principal is $3800.
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The account is earning $1200 per year on a principal of $3800. The interest rate is about 31.6%, an unusually high value.
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<em>Alternate solution</em>
You can recognize that the interest earned in one year is 7400 -6200 = 1200. Since this is simple interest, the amount of interest earned each year is the same, so in 3 years, the account has earned 3×$1200 = $3600 in interest. Then the original principal amount must be ...
$7400 -3600 = $3800 . . . . . principal amount
Y - y₁ = m(x - x₁)
y - 5 = -4(x - (-2))
y - 5 = -4(x + 2)
y - 5 = -4(x) - 4(2)
y - 5 = -4x - 8
+ 5 + 5
––––––––––––
y = -4x - 3
SimplifyingY + -9 = 4(x + -2)
Reorder the terms:-9 + Y = 4(x + -2)
Reorder the terms:-9 + Y = 4(-2 + x)-9 + Y = (-2 * 4 + x * 4)-9 + Y = (-8 + 4x)
Solving-9 + Y = -8 + 4x
Solving for variable 'Y'.
Move all terms containing Y to the left, all other terms to the right.
Add '9' to each side of the equation.-9 + 9 + Y = -8 + 9 + 4x
Combine like terms: -9 + 9 = 00 + Y = -8 + 9 + 4xY = -8 + 9 + 4x
Combine like terms: -8 + 9 = 1Y = 1 + 4x
SimplifyingY = 1 + 4x
36 centimeters, I am not for sure but I think this is correct
