Answer:
D
Step-by-step explanation:
Using trigonometric ratios in the right triangle
tan45° = 1 and cos45° = [tex]\frac{1}{\sqrt{2} }[/tex]
tan45° = [tex]\frac{opposite}{adjacent}[/tex] = [tex]\frac{b}{7}[/tex]
Multiply both sides by 7
7 × tan45° = b, that is
b = 7 × 1 = 7
--------------------------------------------------------
cos45° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{7}{a}[/tex]
Multiply both sides by a
a × cos45° = 7, that is
a × [tex]\frac{1}{\sqrt{2} }[/tex] = 7
Multiply both sides by [tex]\sqrt{2}[/tex]
a = 7[tex]\sqrt{2}[/tex]