In a triangle, the sum of its interior angles is 180°.
A right angle measures 90°.
To find angle B:
53 + 90 + angle B = 180
143 + angle B = 180
angle B = 37
To find lengths AB and AC, you can use trigonometry (sine, cosine, tangent).
1) To find line AB:
sine = opposite/hypotenuse
sin53 / 1 = 10 / x
Cross multiply.
(sin53)(x) = 10
Divide both sides by sin53
x = 12.5213565816 → x = 12.52
Remember your calculator should be in degree mode not radian!
2) To find AC:
tangent = opposite / adjacent
tan37 / 1 = x / 10
(tan37)(10) = x
7.53554050103 = x → 7.54 = x