Answer:
5x² - 20x
Step-by-step explanation:
multiply each term in the parenthesis by the 5x outside
5x(x - 4)
= (5x × x ) + (5x × - 4 )
= 5x² + (- 20x) = 5x² - 20x
porportional means they scale by the same ratio
L / W = L_1 / W_2 = 5.4 / 2.5 = 6.21 / x
solve for x
31 children and 290 adults
Let a = number of adults and c = number of children.
a + c = 321
2a + 1.75c = 634.25
Multiply both sides of the the first equation by -2 and add it to the second equation.
-2a - 2c = -642
(+) 2a + 1.75c = 634.25
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-0.25c = -7.75
Divide both sides by -0.25
c = 31
Use the first equation to find a.
Substitute 31 for c.
a + 31 = 321
Subtract 31 from both sides.
a = 290
Answer: 31 children and 290 adults
