4x + 3y = 54 (1)
3x + 9y = 108 (2)
Multiply (1) by (-3)
-12x - 9y = -162
3x + 9y = 108
---------------------add
-9x = -54
x = 6
plug x = 6 into (1) to find y
4(6) + 3y = 54
24 + 3y = 54
3y = 30
y = 10
Answer
(6 , 10)
Hope it helps.
<span>215,212,736
Round by 10,000 is 215,210,000</span>
Answer:
and 
Step-by-step explanation:
Options
Required
Select the unit rates
Unit rate involve two items where the first item being measured can be any positive number, but the second item must be measured in units (i.e. 1)
For clarity:
If 
represents unit rate, then 
Having said that:
Only and satisfy the condition of unit rates; others are not because they have a denominator other than 1
Answer:
6 minutes
Step-by-step explanation:
'a' in the formula represents altitude in feet. You are told the altitude is 21000 feet, so put that into the formula:
21000 = 3400t +600
You can solve this for t:
20400 = 3400t . . . . . subtract 600 from both sides
6 = t . . . . . . . . . . . . . . . divide both sides by 3400
The problem statement tells you that t represents minutes after lift off, so this solution means the altitude is 21000 feet 6 minutes after lift off.
The question is asking for the number of minutes after lift off that the plane reaches an altitude of 21000 feet, so this answers the question directly:
The plane is at an altitude of 21000 feet 6 minutes after lift off.
Answer:
y = x² + 3x - 40
Step-by-step explanation:
Given the zeros are x = - 8 and x = 5, then the factors are
(x + 8) and (x - 5) and
y = (x + 8)(x - 5) ← expand factors
y = x² - 5x + 8x - 40, hence
y = x² + 3x - 40 ← in standard form
