You would use the distributive property with the negative. So the second x becomes negative, but since the 7 is already negative it becomes positive. Think of it as if you put the two dashes together you can make a plus sign.
Answer:
26
Step-by-step explanation:
add 222 and 20
Answer:
(-4,2)
Step-by-step explanation:
The line going horizontal is the X-axis. And they line going up and down is the y-axis. The way you write the location of a point is (X,Y). Hope this helps!!
Answer:
Step-by-step explanation:
Let's identify what we are looking for in terms of variables. Sandwiches are s and coffee is c. Casey buys 3 sandwiches, which is represented then by 3s, and 5 cups of coffee, which is represented by 5c. Those all put together on one bill comes to 26. So Casey's equation for his purchases is 3s + 5c = 26. Eric buys 4 sandwiches, 4s, and 2 cups of coffee, 2c, and his total purchase was 23. Eric's equation for his purchases then is 4s + 2c = 23. In order to solve for c, the cost of a cup of coffee, we need to multiply both of those bolded equations by some factor to eliminate the s's. The coefficients on the s terms are 4 and 3. 4 and 3 both go into 12 evenly, so we will multiply the first bolded equation by 4 and the second one by -3 so the s terms cancel out. 4[3s + 5c = 26] means that 12s + 20c = 104. Multiplying the second bolded equation by -3: -3[4s + 2c = 23] means that -12s - 6c = -69. The s terms cancel because 12s - 12s = 0s. We are left with a system of equations that just contain one unknown now, which is c, what we are looking to solve for. 20c = 104 and -6c = -69. Adding those together by the method of elimination (which is what we've been doing all this time), 14c = 35. That means that c = 2.5 and a cup of coffee is $2.50. There you go!
Answer:
{x,y} = {-2,2}
Step-by-step explanation:
Solve equation [2] for the variable y
7y = 7x + 28
y = x + 4
Plug this in for variable y in equation [1]
-8x + 4•(x +4) = 24
-4x = 8
Solve equation [1] for the variable x
4x = - 8
x = - 2
By now we know this much :
x = -2
y = x+4
Use the x value to solve for y
y = (-2)+4 = 2
Solution :
{x,y} = {-2,2}
and this intersects at only one point so your answer is A
