Answer:
1st option
Step-by-step explanation:
Given the 2 equations
2x + 5y = 19 → (1)
y = 3x - 3 → (2)
Substitute y = 3x - 3 into (1)
2x + 5(3x - 3) = 19
Answer:
60 minutes for the larger hose to fill the swimming pool by itself
Step-by-step explanation:
It is given that,
Working together, it takes two different sized hoses 20 minutes to fill a small swimming pool.
takes 30 minutes for the larger hose to fill the swimming pool by itself
Let x be the efficiency to fill the swimming pool by larger hose
and y be the efficiency to fill the swimming pool by larger hose
<u>To find LCM of 20 and 30</u>
LCM (20, 30) = 60
<u>To find the efficiency </u>
Let x be the efficiency to fill the swimming pool by larger hose
and y be the efficiency to fill the swimming pool by larger hose
x = 60/30 =2
x + y = 60 /20 = 3
Therefore efficiency of y = (x + y) - x =3 - 2 = 1
so, time taken to fill the swimming pool by small hose = 60/1 = 60 minutes
Answer:
the answer is 9 :)
Step-by-step explanation:
The output k at input t = -7 is -89
Step-by-step explanation:
In order to find the value of a expression on given number, we put the number in given expression in place of independent variable
So,
Given expression is:

It is given that the value of t has to be -7
so putting t=-7 in the expression

Hence,
The output k at input t = -7 is -89
Keywords: Expressions, input, output
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