Answer:
- Dien - 15 seconds, Jane - 10 seconds
Step-by-step explanation:
<u>Together:</u>
- 2/3 of pizza ⇒ 4 seconds
- Full pizza ⇒ 4 ÷ 2/3 = 6 seconds
Dien needs x seconds to eat pizza
Jane needs x - 5 seconds to eat pizza
<u><em>In one second, Dien can eat 1/x, Jane can eat 1/(x - 5), together 1/6 of a pizza</em></u>
- 1/x + 1/(x - 5) = 1/6
- x(x - 5) = 6(x + x - 5)
- x² - 5x - 12x + 30 = 0
- x² - 17x + 30 = 0
- (x - 15)(x - 2) = 0
- x = 15 (x = 2 is discounted as not realistic)
Dien can eat a pizza in 15 seconds, Jane can eat a pizza in 10 seconds
Answer:
x = 50°
Step-by-step explanation:
By vertical angles, we have
50° + 2x = 150°
2x = 100°
x = 50°
Answer:
$149
Step-by-step explanation:
He spent 55 on sneakers at first, then he recieved 30 more, and gave 20 to the mom, which i added to the equation, and what he has left i also added.
Answer:
1) 2x-5 2) -10/x^2
Step-by-step explanation:
Use power rule and constant rule for the first one:
1) f(x)=x^2-5x^1+1 (x^n)'=nx^(n-1) and (c)'=0
f'(x)=2x^1-5(1)x^0+0
f'(x)=2x-5(1) x^0=1
f'(x)=2x-5
Use just power rule for last one after a rewrite
2) f(x)=10/x
f(x)=10x^(-1) now use power rule
f'(x)=-10x^(-2) =-10/x^2
Answer:
C
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 given angles and equate to 180
y + y + 54 = 180
2y + 54 = 180 ( subtract 54 from both sides )
2y = 126 ( divide both sides by 2 )
y = 63° → C
