Answer:
Step-by-step explanation:So we know x + y = 21 and 5x +10y = 165 We line them up in columns x + y = 21 5x +10y = 165 To eliminate the x variable, I'll multiply every element in the 1st equation by -5. -5x + -5y = -105 5x + 10y = 165 Now we combine (add) the equations, which eliminates x altogether. 5y = 60 ... y = 12 From there, x + 12 = 21 ... x = 21-12 ... x = 9 You should double check. Do 9 nickles and 12 dimes equal $1.65? A very important thing to remember using this method is to do the same thing to each element in the equation that you change! I hope that helps.
Add the like terms so (1)(-10i)
Answer:
The slope of a line that is perpendicular to the line
shown in the graph is = 4
Hence, option 'd' is true.
Step-by-step explanation:
From the line equation, let us take two points
Finding the slope between two points




As we know that the slope of the perpendicular line is basically the negative reciprocal of the slope of the line, so
The slope of the perpendicular line will be:

Thus, the slope of a line that is perpendicular to the line
shown in the graph is = 4
Hence, option 'd' is true.
Answer: 46
Step-by-step explanation:
10 (3 +1) + 6
30 + 10 + 6
46
Answer:
It's the last choice:
2x + y - 1 = 0.
Step-by-step explanation:
x - 2y - 3 = 0
Convert to slope-intercept form in order to find the slope:
-2y = -x + 3
y = 1/2x - 3/2
So the slope is 1/2. The slope of a line perpendicular to this is -1 / 1/2 = -2.
Using the point-slope form to find the required equation:
y - y1 = m(x - x1)
x = 4 and y = -7 so we have:
y + 7 = -2(x - 4)
y + 7 = -2x + 8
2x + y - 1 = 0 is the answer.