Answer:
x=3.565
Step-by-step explanation:
Answer:
x = 1 + sqrt(89) or x = 1 - sqrt(89)
Step-by-step explanation:
Solve for x:
(x - 9) (x + 7) = 25
Expand out terms of the left hand side:
x^2 - 2 x - 63 = 25
Add 63 to both sides:
x^2 - 2 x = 88
Add 1 to both sides:
x^2 - 2 x + 1 = 89
Write the left hand side as a square:
(x - 1)^2 = 89
Take the square root of both sides:
x - 1 = sqrt(89) or x - 1 = -sqrt(89)
Add 1 to both sides:
x = 1 + sqrt(89) or x - 1 = -sqrt(89)
Add 1 to both sides:
Answer: x = 1 + sqrt(89) or x = 1 - sqrt(89)
Joanna bought 7 notebooks and 14 pencils
Step-by-step explanation:
Step 1 :
Let x denote the number of notebooks and y denote the number of pencils Joanna bought.
Cost of one notebook = $ 2.30
Cost of one pencil = $1.42
Step 2 :
Total of notebooks and pencils bought = 21
=> x + y = 21 => y = 21-x
Total cost of notebooks and pencils = $35.98
=> 2.3x + 1.42y = 35.98
Substituting y = 21- x here , we have,
2.3x + 1.42 ( 21-x) = 35.98
2.3x + 29.82 - 1.42x = 35.98
0.88 x = 6.16
=> x = 7
y = 21-x = 21-7 = 14
Step 3 :
Answer :
Joanna bought 7 notebooks and 14 pencils
Answer:
a. We need 1/4 for each feeder
b. To fill each feeder we need 1.25 pounds
c. We need 60 ounces to fill three bird feeders
Step-by-step explanation:
Five pounds of birdseed is used to fill 4 identical bird feeders,
a. We divide all the birdseed in 4 feeders, so, we need 1/4 for each feeder.
b. If we use 5 pounds for the 4 feeders, so each feeders will take 1/4 of the 5 pounds
=1/4 x 5=1.25 pounds
c. To fill three bird feeders we have to multiply the amount of pounds by feeder by 3 feeders
=1.25 pounds x 3
= 3,75 pounds
If 16 ounces are a pound
so, 16 x 3.75 = 60 ounces
