Count Static Triangle Static Lenghts , when 1 from them is 4cm shorter than another , when hypotenuse lenght is 20cm Sorry for bad english. can someone tell me how to count this ? i havent bind in school that day
+33661 If this is a right-angled triangle with sides of length x and y and hypotenuse 20, then we have:
x = y - 4 (given) and
x^2 + y^2 = 20^2 (Pythagoras)
Put the first into the second:
(y-4)^2 +y^2 = 20^2 Expand:
y^2 -8y +16 + y^2 = 20^2
2y^2 - 8y -384 = 0 Divide by 2:
y^2 - 4y - 192 = 0 This factors as: (y+12)(y-16)=0
Because the triangle must have positive length sides this means y = 16
So x = 16-4 = 12
The side lengths are 12cm and 16cm
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