Math test and stuff, I need help

How do you find the area of this triangle.

Acamper leaves camp on a kayak and travels 50 miles east on a river, then he ties his kayak to the bank and travels 20 miles north on a bicycle. this trip can be plotted on the coordinate plane, where the camp is the point (0, 0). the distant of the camper to the camp can be found using the distance formula. which other formula can he use? a) 502 - 202 b) 502 + 202 c) 502 - 202 d) 502 + 202

Aplot of land is shaped like a quadrilateral. fences are built on the diagonal to divide the area into 4 sections. what is vi to the nearest tenth? gv = 6.55fv = 5.84vh = 3.27vi = ?