Answer:
a. 90º
Explanation:
The chords ST and RA intesect at Y, so that SY is now perpendicular to RY and they form an angle 90 degrees at that point. However angles mSA and mRT are both at the circumference of the circle(a chord is a line from point of a circle's circumference to the other) and are both 90 degrees because angle at the circumference is half of angle at the centre in same arc.
This may not be very pretty.
(2x + 5) * (2x + 5) expanded is (use foil)
F = 4x^2
O = 2x * 5 = 10x
I = 2x + 5 = 10x
L = 25
Total = 4x^2 + 20x + 25
(x + 3)(x + 3) = x^2 + 6x + 9 by the same method
(2x + 7)(2x + 7) = 4x^2 + 28x + 49 Same method.
4x^2 + 20x + 25 + x^2 + 6x + 9 = 4x^2 + 28x + 49
5x^2 + 26x + 34 = 4x^2 + 28x + 49 Collect everything on the left.
x^2 - 2x - 15 = 0
(x - 5)(x + 3) = 0
x + 3 will have no meaning.
x - 5 = 0
x = 5
2x + 5 = 2*5 + 5 = 15
x + 3 = 5 + 3 = 8
2x+ 7 = 2*5 +7 = 17
Check
15^2 + 8^2 = 17^2
225 + 64 = ? 289
289 = 289
a = 15 <<<<< answer
b = 8 <<<<< answer
c = 17 <<<<< answer
Answer: 125
Step-by-step explanation:
5^3=5*5*5=125
-5^3=(-5)*(-5)*(-5)=25*(-5)=-125
A scale of 8cm:12cm would be a scale of 2/3. since this is the case, we can divide the scale drawing of the playground by the scale factor to get the length of the actual playground
12.4/0.6666 = 18.6
The answer is 18.6
