Answer:
The answer is x = 5.
Explanation:
Given:
Δ ABC is an Isosceles triangle with AB = CA
m∠ ABC = ( 6x + 4 )°
m∠ BAC = 73°
m∠ BCA = ( 8y - 7 )°
To Find:
x = ?
Solution:
Properties of an Isosceles Triangle.
- Base angles or two angles are equal.
- Any two sides are equal.
Here , Δ ABC is an Isosceles triangle with AB = CA
∴ m∠ BAC = m∠ BCA
![73= 8y-7\\8y=73+7\\8y=80\\y=(80)/(10) \\y=10](https://img.qammunity.org/2020/formulas/mathematics/middle-school/k65vzfyekecfd8zjxks3jiq8cn0wj4bi3i.png)
∴ m∠ BCA = ( 8y - 7 )°
= 8 × 10 - 7
m∠ BCA = 73 Which is same as ∠ CAB
Property of a Triangle is Sum of the measures of the angle of a triangle is 180°.
![\angle ACB + \angle CAB + \angle CBA = 180](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ojh3r25xexvrmvphk9z4k9g0n794b13c1s.png)
Substituting the values we get,
![73 + 73 + (6x+4) = 180\\6x+4=180-146\\6x=34-4\\6x=30\\x=(30)/(6) \\x=5\\](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ow0xk6d9nvew9jj96acnts8grz0toaim8q.png)
The answer is x = 5.