Recall that
(x + y)² = x² + 2xy + y²
Then if x + y = √7 and x² + y² = 6, we have
(√7)² = 6 + 2xy ⇒ 2xy = 1
We also have
(x - y)² = x² - 2xy + y²
so that
(x - y)² = 6 - 1 ⇒ (x - y)² = 5
which means x - y has two possible values, √5 or -√5.
Answer:
2 is the closest to 2 3/8
Step-by-step explanation:
I believe the correct answer is false. Quadratic equations that can be solved using the quadratic formula cannot always be solved by factoring. <span>Not </span>all quadratic equations can<span> be </span>solved by factoring<span>. Another method that can be used is completing the square. Hope this answers the question.</span>
Answer:
36.5
Step-by-step explanation:
y= -x²+73x-520
which can be represented as ax²+bx+c
a= -1, b= 73, c = -520
for maximum value of y,
the formula is
c - (b² / 4a)
= -520 - (73² / 4×(-1))
= -520 - (5329 / -4)
= -520 + 1332.25
= 812.25
Solving for x,
812.25 = -x²+73x-520
or, x²-73x+ 1332.25 = 0
Solving,
x= 36.5
