Question

I need helpp pleaseee!!
Find the measure of Angle B

Answer 1

B=78

Explanation:

2x+4+2x-9+x=180

5x-5=180

5x=185

x=37

therefore B=78

Answer 2

∠B = 78°

Explanation:

The sum of the measures of the interior angles of a triangle is 180°.

The measurements of the triangle are ∠A = (2x - 9)°, ∠B = (2x + 4)°, and ∠C = x°.

Equation: (2x - 9) + (2x + 4) + x = 180

Step 1: Combine like terms.

`\implies 2x + 2x + x- 9 + 4 = 180`

`\implies 5x - 5 = 180`

Step 2: Add 5 to both sides.

`\implies 5x - 5 + 5 = 180 + 5`

`\implies 5x = 185`

Step 3: Divide both sides by 5.

`\implies (5x)/(5) = (185)/(5)`

`\implies x = 37`

Step 4: Substitute 37 as the value of x in ∠A, ∠B, and ∠C to find their measures.

`\angle {\sf A} \implies 2(37) - 9 = 65`

`\angle {\sf B} \implies 2(37) + 4 = 78`

`\angle {\sf C} \implies 37`

The measure of the angles are: ∠A = 65°, ∠B = 78°, and ∠C = 37° . Together, they add up to 180°.