I think that C and D are the correct answers
Answer:
x= 4 y= 7 z= -6
Step-by-step explanation:
solve for one and you get them all
First, I got rid of the z by multiplying common factors (multiplied z by 2) and added equations 2 and 3 together after multiplying by 2
4x - 3y - 2z = 7
-10x+10y+2z= 18
-6x+7y= 25
Then multiplied z by -3 (to get rid of the z) with the original equation 3
3x - 2y + 3z = -20
15x-15y-3z= -27
18x-17y= -47
Next find common thing between the 2 equations we got and multiply it by that and combine (we can multiply first equation by 3 to get rid of the x and solve for y)
-18x+21y= 75
18x-17y= -47
y=7
Work backwards, substitute 7 into the above equation, you get x= 4 and then same for z to get z= -6
It would be 23 girls if you divide 46 by 2 since your trying to figure out the amount of boys for 46 girls.
Slope of AB=(2-3)/(1+1)=-1/2; AC=(-1-3)/(-3+1)=-4/-2=2; BC=(-1-2)/(-3-1)=-3/-4=3/4.
The product of two sides that are perpendicular is -1. Slopes of AB and AC are perpendicular so angle A is a right angle. ABC is a right-angled triangle.
