Answer:
1.) (11, -7/3), 2.) No solution. 3.) (1, 3)
Step-by-step explanation:
1.)
2x + 3y = 15
x - 3y = 18
Solve...use elimination method
2x + x + 3y - 3y = 15 + 18
3x = 33
x =11
11 - 3y = 18
-3y = 7
y = -7/3
(11, -7/3)
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2.) y = 4x + 4
y = 4x - 4
Use substitution.
4x + 4 = 4x - 4
4 = -4 FALSE NO Solution
3.) y = 5- 2x
4x + 3y = 13
Can use elimination method
2y = 10 - 4x
add it to 4x + 3y = 13
10 + 3y = 2y + 13
y = 3
3 = 5 - 2x
x = 1
(1, 3)
Marked down by 35%
this decreased it by 115.65
thhat means that 115.65 is 35% of original
find original
35%=35/100=7/20
'of' means multiply
115.65=7/20 times original
multiply both sides by 20/7 to clear fraction (20/7 times 7/20=140/140=1)
2313/7=original
330.428=original
round
330.43
original price=$330.43
Answer:
x = -2 , y = 4
Step-by-step explanation:
given:
5x + 2y = -2 <em>*4</em>
4x + 3y = 4 <em>*5</em>
Solving simultaneously,
20x + 8y = -8 ....eq 1
(-) 20x +15y = 20 ...eq 2
.............................................
-7y = -28
y = -28 / -7
y = 4
using equation 2,
20x +15(4) = 20
20x = -40
x = -2
That would be 30 minutes since 2 1/2 hours equals 150 minutes, a fifth of 150 is 30.
1
3.50
3.50
+3.50
______
10 .50
