Write two equations relating the measure of <4 to the measures of <1,<2, and <3

Find the domain of the following expression: 1/(√x)-2

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.

Non-euclidean geometry was discovered when, in seeking cleaner alternatives to the fifth postulate, it was found that the negation could also be true a. true b. false