Answer: x = -0.2651 and y = -0.9759
Step-by-step explanation:
Solution by substitution method
8x+5y= -7
-7x+6y= -4 = 7x-6y=4
Suppose,
8x+5y=-7→(1)
7x-6y=4→(2)
Taking equation (1), we have
8x+5y= -7
⇒8x= -5y -7
⇒x= -5y-7 / 8 →(3)
Putting x= -5y-7 / 8
in equation (2), we get 7x-6y=4
7(-5y-7/8)-6y=4
⇒-35y-49-48y=32
⇒-83y-49=32
⇒-83y=32+49
⇒-83y=81
⇒y= 81 / -83
⇒y= -0.9759→(4)
Now, Putting y= -0.9759 in equation (3), we get
x= -5y-7
x= -5(-0.9759)-7/8
⇒x= 4.8795-7/8
⇒x= -2.1205/8
⇒x= -0.2651
∴x= -0.2651 and y = -0.9759
50 divided by 8 = 6.25
1oz perfume = $6.25
110 divided by 17 = 6.4705
1oz perfume = $6.4705
Therefore the second option is cheaper
It would have to be letter D my guy, if you know what centuries and decades are this is easy
D= # of dimes
q= # of quarters
QUANTITY EQUATION:
d + q= 64
COST EQUATION:
0.10d + 0.25q= $9.25
STEP 1:
multiply quantity equation by -0.10 to be able to eliminate the d term in step 2
(-0.10)(d + q)= (-0.10)(64)
-0.10d - 0.10q= -6.40
STEP 2:
add equation from step 1 to cost equation to eliminate the d term and solve for q
Add
0.10d + 0.25q= $9.25
-0.10d - 0.10q= -6.40
0.15q= 2.85
divide both sides by 0.15
q= 19 quarters
STEP 3:
substitute q value in step 2 into either original equation to find d value
d + q= 64
d + 19= 64
subtract 19 from both sides
d= 45 dimes
CHECK:
0.10d + 0.25q= $9.25
0.10(45) + 0.25(19)= 9.25
4.50 + 4.75= 9.25
9.25= 9.25
ANSWER: There are 45 dimes and 19 quarters.
Hope this helps! :)
Answer:
w = -10
Step-by-step explanation:
w + 4 = (-6)
Subtract 4 from each side
w+4-4 = -6-4
w = -10
