Step-by-step explanation:
400 meters is standard lap distance for a race track. 2 x 50 meters is lap distance in International pools. A lap of 440 yards is 1/4 mile. So 4 laps/mile.
8/12 4/8 4/12 is the answer for the shaded part
Let's first write the equation given
x²+6x-13=0
They have told us to use "Completing the square" method.
So we need write x²+6x-13 as a whole square.
x²+6x-13=0
x²+(2*3*x)-9-4 = 0
x²+(2*3*x)-3²=4
Now we can write the LHS as:
(x - 3)²=2²
Hence,
x-3 can either be 2 or -2
Now,
x - 3=2
x=5
Or,
x - 3=-2
x=1
Therefore now we know that x can either be 1 or 5. So the correct answer is Option B.