For a quadratic equation ax^2 + bx + c = 0, the discriminant is given by b^2 - 4ac
Thus for a^2 - 2a + 5 = 0,
a = 1, b = -2 and c = 5
b^2 - 4ac = (-2)^2 - 4(1)(5) = 4 - 20 = -16
17 = 5k-2
+2 +2 The first step is to add 2 to both sides
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19 = 5k Then you divide both sides by 5
The answer is 3.8 = k
A possible answer is

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Pi is an irrational number and when you multiply a rational number with an irrational number, you end up with an irrational number.
Answer:
p=75(alternative) , t=105(sum of all sides) ,
q=105(sum of all sides) , s=105(straight angle)
r=75(sum of all sides)