Complete question:
Joel has a goal to practice his clarinet for 4 1/2 per week. The list below shows the number of hours Joel has a practiced so far for the week. Monday 1 1/2 hours Wednesday 1 1/4 hours Thursday 1 hour How many more hours does he need to practice this week to meet his goal
Answer: 3/4 hours
Step-by-step explanation:
Target hours = 4 1/2 hours = 9/2 hours
Number of hours so far :
(1 1/2 + 1 1/4 + 1) = (3/2 + 5/4 + 1) hours
Total so far :
L. C. M of denominator = 4
(6 + 5 + 4) /4 = 15/4
Number of hours left to meet his target equals :
Target hours - total so far
( 9/2 - 15/4)
L. C. M of denominator = 4
(18 - 15) / 4 = 3/4 hours
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First thing you should do is reduce coefficients.
1st equation has all multiples of '2'. Divide by 2
---> x +3y = -6
2nd equation has multiples of 5. Divide by 5.
---> x - y = 2
Now elimination part is easier.
Eliminate 'x' variable by subtracting 2nd equation from 1st.
x + 3y = -6
-(x - y = 2)
----------------------
4y = -8
Solve for 'y'
4y = -8
y = (-8)/4 = -2
Substitute value for 'y' back into 2nd equation:
x - (-2) = 2
x + 2 = 2
x = 0
Solution to system is:
x=0, y =-2
Answer:
1 is the constant
Step-by-step explanation:
Answer C : 3x^2+7xy-2y^2
equivalent to the following expression
Combine like terms
2x^2 + x^2 is 3x^2
4xy+3xy is 7xy
-y^2-y^2 is -2y^2
So expression becomes
Answer C is correct
