Answer:
x = 25
scalene, acute
Explanation:
Sum of the interior angles of a triangle = 180°
![\implies (2x+11)+(3x-7)+(2x+1)=180](https://img.qammunity.org/2023/formulas/mathematics/middle-school/2n40km4hkm4e6pmc3yfe87254224j8or5u.png)
![\implies 2x+11+3x-7+2x+1=180](https://img.qammunity.org/2023/formulas/mathematics/middle-school/ez06epdh00tldby9sqfj0nqd9f0xsgjxc3.png)
Collect like terms:
![\implies 2x+3x+2x+1+11-7=180](https://img.qammunity.org/2023/formulas/mathematics/middle-school/smep995ddgs2y708jsp4gg5cs0miadee22.png)
Combine like terms:
![\implies 7x+5=180](https://img.qammunity.org/2023/formulas/mathematics/middle-school/ktfu17c295jry5qvgooigivos5q5sa3r5m.png)
Subtract 5 from both sides:
![\implies 7x=175](https://img.qammunity.org/2023/formulas/mathematics/middle-school/5dl1615vmhvdh29tzydjyh57urpk0hrwnz.png)
Divide both sides by 7:
![\implies x=25](https://img.qammunity.org/2023/formulas/mathematics/middle-school/zaws6bnhv7jye6t7e2bqkc2fah97yn9voa.png)
Substituting found value of
into the three angle expressions:
∠A = (2 x 25) + 11 = 61°
∠B = (3 x 25) - 7 = 68°
∠C = (2 x 25) + 1 = 51°
This is a scalene triangle as it has three different angles and three different side lengths (non-congruent).
It is also an acute triangle as all interior angles are less than 90°