Answer:
13/-3
Step-by-step explanation:
Answer:
u > - 7
Step-by-step explanation:
7u - 32 < - 3(6-3u)
7u - 32 < - 18 + 9u
18-32 < - 7u + 9u
-14 < 2u
2u > - 14
u > - 7
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.
Well 1/2 is one quarter of 2 hours. so if he can paint 180 square feet is 1/2 hour multiply it by four to get 2 hours. so 180 times 4 is 720.
He can paint 720 square feet in 2 hours
(4^1/2)^5= 4^(1/2)*4^(1/2)*4^(1/2n)*4^(1/2)*4^(1/2)=
2*2*2*2*2= 32
16^(-5/4) = 0.03125
(1/4)^(3/2)= 0.125
