Starting off, we can multiply the third equation by 2 and add it to the third to get rid of both the x and y variables. Next, we get z=1. Plugging that into 3y-5z=-23, we get 3y-5=-23. Adding 5 to both sides, we get 3y=-18. After that, we can divide both sides by 3 to get y=-6. Plugging that into -2x-y-z=-3, we get -2x+6-1=-3=-2x+5. Subtracting 5x from both sides, we get -2x=-8. After that, we can divide both sides by -2 to get x=4.
2(x-3)=7x-31
2x-6=7x-31
-7x -7x
----------------
-5x-6=-31
+6 +6
--------------
-5x=-25
Divide by -5
x=5
3x-2(x+5)=-3+18
15
3x-2(x+5)=15
3x-2x-10=15
x-10=15
+10 +10
--------------
x=25
Answer:
(2z + 5)(2z - 3)
Step-by-step explanation:
4z² + 4z - 15
4z² + 10z - 6z - 15
2z (2z + 5) - 3 (2z + 5)
(2z + 5)(2z - 3)
Answer:
c. 7.527
Step-by-step explanation:
We know that 78 percent of the bar is gold and the total weight is 9.65 ounces. Just multiply the total weight by 78%.
9.65(0.78)=7.527