Let the second side be x
then,
first side = twice the length of the second side
= 2x
third side = 20 feet less than three times the second side
3 (second side ) - 20
= 3 (2x) -20
= 6x - 20
perimete of a triangle = sum of all sides,
substitute the values we know,
and you'll be left with this equation
106 = x + 2x + 6x - 20
106+ 20 = 9x
126 = 9x
126/9 = x
14 = x
so,
measure of second side = x = 14 feet
measure of first side = 2x = 2 (14) = 28 feet
measure of thurd side = 6x - 20 = 6 (14)-20 = 84- 20 = 64 feet.
Answer:
x = 15°
Step-by-step explanation:
<em><u>The segment is a diameter, So let us assume the part in which there lies the triangle as a semicircle.</u></em>
=> <em>A triangle inscribed in a semi-circle will always have one of its angle equal to 90</em>
=> <em>So the angle (not 75 and x) is 90 degrees.</em>
<em>=> To find the value of x, we'll subtract rest of the angles from 180 degrees (because the interior angles of a triangle add up to 180°)</em>
<em>So,</em>
=> x = 180-90-75
=> x = 15°
25% = 25/100 = 0.25
9*0.25 = 2.25.
You save $2.25 with the discount.
Oldest = 2 times Youngest -> O = 2*Y
Middle = Youngest + 5 -> M = Y+5
All of them together is 57 -> O + M + Y = 57
So you have these three equations:
(1) O = 2*Y
(2) M = Y+5
(3) O + M + Y = 57
Now you want to reduce the number of variables. You can change the second equation to be Y = M-5 and then plug in "M-5" wherever there is currently a Y:
(4) O = 2*(M-5) = 2*M - 10
(5) O + M + (M-5) = 57
which becomes O + 2M = 62
Then you plug in the "O" equation (4) into (5) which gives you
(2M-10) + 2M = 62 which reduces to 4M = 72.
So now I know M is 18.
I can now plug that into my other equations:
(4) O = 2*18 - 10 which means O = 26.
Now I plug that into (1) from the top:
26 = 2*Y which becomes 13 = Y
So now I have O, Y, and M
Oldest is 26
Middle is 18
Youngest is 13
Reading the sentence again, you can see that this makes sense.
