Answer:
x =3
Step-by-step explanation:
3(4x + 4) = 2(5x+9) - 12
First step is to open the brackets by multiplying. It becomes
3×4x + 3×4 = 2×5x + 2×9 -12
12x + 12 = 10x + 18 - 12
Collecting like terms on the right hand side and left hand side of the equation, it becomes
12x -10x = 18 -12 -12
2x = -6
Negative sign on the right hand side of the equation overwhelms the positive sign on left hand side of the equation. It becomes
2x = -6
x = -6/2 = -3
Checking
3(4×-3 + 4) = 2(5×-3+9) - 12
-24 = -12-12= -24
So x = -3
Answer:
7. x = 3
Step-by-step explanation:
To find the value of x, use the triangle sum property. Every triangle has interior angles which add to 180 degrees. To solve, add the expressions and numbers together then set equal to 180. Then use inverse operations to solve for x.
7. 20x - 9 + 10x + 9 + 90 = 180 Subtract 90 from both sides.
20x - 9 + 10x + 9 = 90 Add -9 + 9 = 0
20x + 10x = 90 Add like terms 20x + 10x = 30x
30x = 90 Divide both sides by 30.
x = 3
Repeat this process for each problem.
The 3rd one because of the laws and newton’s ways
"Understand the problem" might rightly consist of
• Perform this step first
• Identify what you are being asked to solve or find.
• Identify the important words or numbers in the problem
• Identify any instructions that you are supposed to follow
_____
One of my professors always insisted we start the solution of any problem by writing down what was Given, and what we had to Find, using those headers for the sections of the paper we turned in. Only after those were listed were we allowed to write the Solution. Solution papers that didn't have that format were tossed in the trash, and no credit was given. Harsh, but effective.
