i will give 50 points and brainliest

Answer:
[tex] \boxed{\sf Height \ of \ the \ triangle = 16.5 \ mm} [/tex]
Given:
Area of the triangle = 69.3 mm²
Base of the triangle = 8.4 mm
To Find:
Height of the triangle
Step-by-step explanation:
[tex]\sf \implies Area \ of \ the \ triangle = \frac{1}{2} \times Base \times Height \\ \\ \sf \implies 69.3 = \frac{1}{2} \times 8.4 \times Height \\ \\ \sf \implies 69.3 = \frac{1}{ \cancel{2}} \times \cancel{2} \times 4.2 \times Height \\ \\ \sf \implies 69.3 = 4.2 \times Height \\ \\ \sf \implies 4.2 \times Height = 69.3 \\ \\ \sf \implies Height \times \frac{ \cancel{4.2}}{ \cancel{4.2}} = \frac{69.3}{4.2} \\ \\ \sf \implies Height = \frac{16.5 \times \cancel{4.2}}{ \cancel{4.2}} \\ \\ \sf \implies Height = 16.5 \: mm[/tex]