Beginner help question on finding the tangent point

I'm trying to design a quarterpipe in Librecad but don't have much experience and i'm running into 1 problem i cant seem to fix.
I need a circle with radius 180 to intersect on 2 points the bottom of the circle needs to intersect with the bottom line and then i need it to intersect with the point i've highlighted with the green arrow.
anyone got any clue how i can do this?

Hi,

from the point, using it as center, create an auxiliary circle with the desired radius
from the base line, create a parallel with the radius distance
use the intersections of circle and parallel as center of the desired circle, select which intersection is the needed one.
remove the parallel and the auxiliary circle.

HTH
Perer