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Answer:
- (x +1)² = 4
- (D) x = -1 ±2
Step-by-step explanation:
Start by getting the x-terms on one side of the equal sign. We can do that by subtracting x from both sides.
3 = x² +2x
Now, add the square of half the x-coefficient.
3 +1 = x² +2x +1
(x +1)² = 4 . . . . . . . . write as a square in the desired form
__
To solve, take the square root, and add the opposite of the left-side constant.
x +1 = ±2
x = -1 ±2 . . . . . . matches choice (D)
Tan 2 pi/3= (sin2pi/3)/(cos2pi/3)= (sqrt 3)/2 dividend by (-1/2)= - sqrt 3
f(2) is greater than g(2) and f(-2) is less than g(-2)
The grocer wants to make a 10 pound mixture
p - pounds of peanuts
c - pounds of cashews
therefore the total pounds should be equal to 10 pounds
p + c = 10 -----> 1)
the cost for ;
peanuts - 4.00 per pound * p pounds = 4p
cashews - 6.50 per pound * c pounds = 6.5c
the price of 10 pounds mixture = 4.75 per pound * 10 pounds = 47.5
4p+6.5c = 47.5 ---> 2)
to solve for p and c lets use simultaneous equations
p + c = 10 -----> 1)
4p+6.5c = 47.5 ---> 2)
multiply 1st equation by 4
4p + 4c = 40 ---> 3)
subtract 3rd equation from the 2nd
2.5c = 7.5
c = 3
substituting c= 3 in 1st equation
p+c = 10
p+3 = 10
p = 7
therefore 3 pounds of cashews and 7 pounds of peanuts are needed to make the mixture