Answer: x^2 + 9x + 20
Step-by-step explanation:
Foil Method: (a + b) (c + d) = ac + ad + bc + bd
Lets say:
a = x
b = 5
c = x
d = 4
Plugging in the numbers: xx + 4x + 5x + 5*4
Combine like terms:
xx = x^2
4x + 5x = 9x
5 * 4 = 20
You're then left with: x^2 + 9x + 20
Ax^2+bx=c
REMEMBER THIS
ok
first, make sure that a is 1
done
now take 1/2 of b and square it
-18/2=-9, (-9)^2=81
add that to both sides
x²-18x+81=19+81
x²-18x+81=99
factor perfect square
(x-9)²=100
square root both sides
don't forget positive and negative root
x-9=10
x-9=-10
ad 9 to both sides
x=19
x=-1
answer is -1; 19
2nd choice is answer
Step-by-step explanation:
2.9 hours = 174mins
174 mins = 4.9miles
1 miles = 1740/49 mins
8.73 miles = 310.0mins (1dp)
Topic: Rate & Proportions
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Answer:
$95,600
Step-by-step explanation:
the question can be rephrased as '4780 is five percent of what number'?
we can use the ratio of 'is/over' = %/100 to solve
'is' = 4780
'of' = selling price of house ('p')
4780/p = 5/100
now cross-multiply:
5p = 478000
p = 95600
