Right off the bat, we can notice that Angle ABD is a right angle. This means that it must add up to 90 degrees. Therefore, we can write that:
![(5x+3)+(3x+7) = 90](https://img.qammunity.org/2019/formulas/mathematics/high-school/r7znp302hl3ajpkmx8p4rj7r06svuorag4.png)
Let's combine like terms:
![8x+10=90](https://img.qammunity.org/2019/formulas/mathematics/high-school/nsduj2vpp4fg71q2vybnnksobsvz10rj8x.png)
Solve for x:
![8x=80](https://img.qammunity.org/2019/formulas/mathematics/high-school/i7prdredkdb6oac4ggwja6zh84121opbmh.png)
![x = 10](https://img.qammunity.org/2019/formulas/mathematics/high-school/51srwvziwzj2zyescsgpvlzi7ty9pwrh0h.png)
Now, since we need to find the measure of angle ABC which is given by (5x+3), we can plug the newly found value of x in to figure it out:
![5(10)+3 = 53](https://img.qammunity.org/2019/formulas/mathematics/high-school/82kqnhcifn7wa72u7jcmi0xcy3bj0uk4gc.png)
Therefore,
Angle ABC = 53°.