Answer:
x = 10
I used the Interior Angles of a Triangle Rule --The sum of all 3 interior angles in a triangle is always 180°.
(3x + 28) + (5x - 18) + 90° = 180°
Now i can get rid of the parentheses and combine like terms.
3x + 5x + 28 - 18 + 90 = 180
8x + 10 + 90 = 180
8x + 100 = 180
Then i subtract 100 from both sides to isolate x.
8x + 100 - 100 = 180 - 100
8x = 80
Then, i divide both sides by 8 to find x.
8x ÷ 8 = 80 ÷ 8
x = 10
That is maybe how and my teacher told me that if you have a whole number you can add a line underneath it
Answer:
x = 1 or x = -5/2
Step-by-step explanation:
Solve for x over the real numbers:
2 x^2 + 3 x - 2 = 3
Divide both sides by 2:
x^2 + (3 x)/2 - 1 = 3/2
Add 1 to both sides:
x^2 + (3 x)/2 = 5/2
Add 9/16 to both sides:
x^2 + (3 x)/2 + 9/16 = 49/16
Write the left hand side as a square:
(x + 3/4)^2 = 49/16
Take the square root of both sides:
x + 3/4 = 7/4 or x + 3/4 = -7/4
Subtract 3/4 from both sides:
x = 1 or x + 3/4 = -7/4
Subtract 3/4 from both sides:
Answer: x = 1 or x = -5/2