Given:-
A 1.8m long ladder rests against a vertical wall. The ladder makes an angle of 23 degrees with the wall.
To find How high up the wall does the ladder go.
So now we use the formula,
![\cos \theta=\frac{\text{adjacentside}}{\text{hypotneus}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/178fdzem0zfwoasv7vzp3g823fiav46360.png)
So now we substitute the known values. so we get,
![\cos 23=(x)/(1.8)](https://img.qammunity.org/2023/formulas/mathematics/high-school/lnu0iwhtpqy83hkmve84g8p28u8yc1cohu.png)
So now we simplify. so we get,
![\begin{gathered} x=\cos 23*1.8 \\ x=0.920*1.8 \\ x=1.656 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/jhytyc181zvzygv6hkaqd0kvx1bpd0r4v5.png)
So the required height is 1.65m