Answer: 12 hours
Step-by-step explanation:
Given : Working together, it takes Sam, Jenna, and Francisco two hours to paint one room.
When Sam works alone, he can paint one room in 6 hours. When Jenna works alone, she can paint one room in 4 hours.
Let 't' be the time taken by Francisco to paint one room on his own.
Then , we have
Rate of work of Sam +Rate of work of Jenna + Rate of work of Francisco =Rate of work they all do together
i.e. 
i.e. 
i.e. 
i.e. 
i.e. 
i.e. 
i.e. t= 12
Hence, Francisco would take 12 hours to paint one room on his own.
Answer:
x*(x+2)= 63 7 and 9
Step-by-step explanation:
Answer:
Step-by-step explanation:
<u><em>The complete question is</em></u>
A chef bought $17.01 worth of ribs and chicken. Ribs cost 1.89 per pound and chicken costs 0.90 per pound. The equation 0.90 +1.89r = 17.01 represents the relationship between the quantities in this situation.
Show that each of the following equations is equivalent to 0.9c + 1.89r = 17.01.
Then, explain when it might be helpful to write the equation in these forms.
a. c=18.9-2.1r. b. r= -10÷2c+9
we have that
The linear equation in standard form is
where
c is the pounds of chicken
r is the pounds of ribs
step 1
Solve the equation for c
That means ----> isolate the variable c
Subtract 1.89r both sides
Divide by 0.90 both sides
Simplify
step 2
Solve the equation for r
That means ----> isolate the variable r
Subtract 0.90c both sides
Divide by 1.89 both sides
Simplify
therefore
The equation is equivalent
The equation is helpful, because if I want to know the number of pounds of chicken, I just need to substitute the number of pounds of ribs in the equation to get the result.
Yo sup??
Area of trapezium=1/2*(sum of opposite sides)*(height of trapezium)
=1/2*(12.5+17.5)*6
=1/2*30*6
=90 cm²
Therefore the correct answer is option A
Hope this helps.
Answer:
x = 3
Step-by-step explanation:
3(10-x)=21
30-3x=21
-30 -30
-3x=-9
x=3
