#5tantheta=7#
#"isolate "tantheta" by dividing both sides by 5"#
#(cancel(5) tantheta)/cancel(5)=7/5#
#rArrtantheta=7/5=1.4#
#"we now want the angle whose tangent is 1.4"#
#"this is expressed as "#
#theta=tan^-1(1.4)#
#"using the 'shift' key on your calculator"#
#"press 'shift' then tan 1.4 to obtain angle in degrees"#
#rArrtheta=tan^-1 1.4=54.5^@" to 1 dec. place"#
#color(blue)"ensure your calculator is set to degree mode"#
#"using CAST in quadrant diagram"#
#"tells us that tan is positive in first/third quadrant"#
#"the angle above is in the first quadrant"#
#"the other angle is in the third quadrant"#
#5tantheta=7" therefore has 2 solutions"#
#"that is "theta=54.5^@larrcolor(blue)"in first quadrant"#
#"or "theta=(180+54.5)^@=234.5^@larrcolor(blue)"in third quadrant"#
