Since 2.5% as a decimal is .025, the equation to get this is:
(.025)(80000)
Once multiplied, these equal 2,000. Or in other words, the Smiths pay $2,000 in school taxes per year.
There are two probabilities of the solution. First if 80° acts as one of the leg angles, second if 80° acts as the vertex angle.
FIRST PROBABILITY
If 80° is one of the leg angles, then the other angle would be 80° too, because iscosceles has two congruent angles on the leg.
Find the vertex angle
the sum of interior angles in a triangle is 180°
vertex angle + angle on the leg + angle on the leg = 180°
vertex angle + 80° + 80° = 180°
vertex angle + 160° = 180°
vertex angle = 180° - 160°
vertex angle = 20°
The interior angles are 80°,80°,20°
SECOND PROBABILITY
If 80° is the vertex angle, we should find the value of the two leg angles. The two legs has congruent angles.
Find the leg angles
the sum of interior angles in a triangle is 180°
leg angle + leg angle + vertex angle = 180°
2 × leg angle + vertex angle = 180°
2 × leg angle + 80° = 180°
2 × leg angle = 180° - 80°
2 × leg angle = 100°
leg angle = 50°
The interior angles are 80°, 50°, 50°
Solve:
"<span>twice the number minus three times the reciprocal of the number is equal to 1."
3(1)
Let the number be n. Then 2n - ------- = 1
n
Mult all 3 terms by n to elim. the fractions:
2n^2 - 3 = n. Rearranging this, we get 2n^2 - n - 3 = 0.
We need to find the roots (zeros or solutions) of this quadratic equation.
Here a=2, b= -1 and c= -3. Let's find the discriminant b^2-4ac first:
disc. = (-1)^2 - 4(2)(-3) = 1 + 24 = 25.
That's good, because 25 is a perfect square.
-(-1) plus or minus 5 1 plus or minus 5
Then x = ------------------------------ = --------------------------
2(2) 4
x could be 6/4 = 3/2, or -5/4.
You must check both answers in the original equation. If the equation is true for one or the other or for both, then you have found one or more solutions.</span>
A. y=5+1.5d
b. after 20 days it will be 5+ 1.5 × 20 = 5+ 30= 35 cm
of the shaded portion.