1. 4x + 8y = 12....divide by 4
x + 2y = 3
2y = -x + 3
y = -1/2x + 3/2...slope is -1/2, y int is 3/2
x + 2y = -3
2y = -x - 3
y = -1/2x - 3/2...slope is -1/2 and y int is -3/2
when the slopes are the same, and the y int are different, then the lines are parallel and never intersect...so they have no solution and are inconsistent
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2. y = 2x - 1...slope is 2 and y int is -1
y = -2x + 5 ...slope is -2 and y int is 5
when the slopes are different and the y int are different, then there is 1 solution making it independent
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3. 4x - 12y = 8...divide by 4
x - 3y = 2
same as other equation meaning the equations are the same line...meaning they have infinite solutions making them dependent
Answer:
x = 21/2
y = -19/2
Step-by-step explanation:
5x - 17 = 4y + 7x
5x - 7x - 4y = 17
-2x - 4y = 17
6x + 8y = - 13
-2x - 4y = 17 | ×2 |
6x + 8y = - 13 | ×1 |
-4x - 8y = 34
6x + 8y = - 13
___________+
2x = 21
x = 21/2
-2x - 4y = 17
-2(21/2) - 4y = 17
-21 - 4y = 17
-4y = 17 + 21
-4y = 38
y = -38/4
y = -19/2
Answer:
75 km
Step-by-step explanation:
Given the following :
Scale on first map = 1cm to 20 km
Distance fromFresno to San Francisco = 15km on first map
Scale on 2nd map = 1cm to 100 km
1cm / 20km = 15km
Let of Distance from Fresno to San Francisco on 2nd map = d
1cm / 100km = d
1 : 20 = 15
1 : 100 = d
20/ 100 = 15/d
1/5 = 15/d
d = 15 * 5
d = 75 km
