Answer:
d.12
Step-by-step explanation:
its saying she ate 3 an now has 9. so you really add 3 to 9 an your answer is 12. in other words x=9+3 for your level of math. i'll be glad to help her with her home work for now if you would like me to.
Combine the 2nd and 3rd equations. 3x will disappear:
2y + 5z = 7 This is true for any y and z, and is independent of x.
7-5z
Solving for y, 2y = 7 - 5z, so that y = ---------
2
We have to eliminate x again by using the 1st and 2nd equations:
-2x - 6y - 2z = -2. We want the coeff. of x in the first eqn to be -3.
Therefore, mult. all terms of -2x - 6y - 2z = -2 by 3/2:
(3/2)(-2x - 6y - 2z = -2) = -3x -9y -3z =-3
Now add this version of the 1st row to the 2nd row:
-3x -9y -3z =-3
3x +2y +5z = 7
----------------------
-7y + 2z = 4
7 - 5z
We found earlier that y = ----------, and can elim. y by subst. this fraction into
2
-7y + 2z = 4. Then -7y + 2z = 4 becomes -7( (7-5z)/2 ) + 2Z = 4.
Elim. the fraction by mult. all terms by 2:
-7(7-5z) + 4z = 8 which becomes -49 + 35z + 4z = 8
so that 39z = 57, and so z = 57/39.
Subst. this back into -7y + 2z = 4 to calculate y. Make a final subst. to calculate x.
Given the choice, I would solve this system using matrices.
Turns out that the solution, using matrices, does not exist.
Answer:
11.4
Step-by-step explanation:
You find the square root
Answer:
mid point=(-1/2,-5)
Step-by-step explanation:
