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
8x^3 - 6x^4 + 12x^3
Answer:
The correct answer is option C
a = 10√3, b = 5√3, c = 15 and d = 5
Step-by-step explanation:
Points to remember
The angles of a right angled triangle, 30°, 60° and 90° then sides are in the ratio, 1: √3 : 2
<u>To find the value of variables</u>
From the figure we can see 2 right angled triangle with angle 30, 60 and 90
we get, d= 5 then b = 5√3
b = 5√3 the c = 5√3 * √3 = 15
and a = 2 * 5√3 = 10√3
Therefore the correct answer is option C
a = 10√3, b = 5√3, c = 15 and d = 5
42000000000000000
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