Basically, like this:
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Answer:Although the Quadratic Formula always works as a strategy to solve quadratic equations, for many problems it is not the most efficient method. Sometimes it is faster to factor or complete the square or even just "out-think" the problem. For each equation below, choose the method you think is most efficient to solve the equation and explain your reason. Note that you do not actually need to solve the equation. a. x2+7x−8=0x
2
+7x−8=0, b. (x+2)2=49(x+2)
2
=49, c. 5x2−x−7=05x
2
−x−7=0, d. x2+4x=−1x
2
+4x=−1.
Answer:
(x, y) = (77/240, -3/10)
Step-by-step explanation:
It is convenient to write the equations in standard form.
Multiplying the first equation by 21 gives ...
21y = 24x -14
Multiplying the second equation by 8 gives ...
24x +9y = 5
Then the system of equations in standard form is ...
Subtracting the first from the second, we get ...
(24x +9y) -(24x -21y) = (5) -(14)
30y = -9
y = -9/30 = -3/10
Substituting this into the second equation, we have ...
24x +9(-3/10) = 5
24x = 7.7 . . . . . . . add 27/10
x = 7.7/24 = 77/240
The solution is (x, y) = (77/240, -3/10).
Answer:
It is decreased by $80,000
Step-by-step explanation:
