We know that the area of triangle

= 1/2 x base x height

In first row,

base = 15 cm and area = 87 cm^{2}

87 =1/2 x 15 x height

⇒ height =(87 x 2)/15

= 11.6 cm

In second row, height = 31.4 mm and area = 1256 mm^{2}

\ 1256 = 1/2 x base x 31.4

⇒ base = (1256 x 2)/31.4

=80 mm

In third row,

base = 22 cm and area = 170.5 cm^{2}

170.5 = 1/2 x 22 x height

⇒ height = (170.5 x 2) /22

=15.5 cm

Thus, the missing values are:

Base | Height | Area of triangle |

15 cm | 11.6cm | 87 cm^{2} |

80 mm | 31.4 mm | 1256 mm^{2} |

22 cm | 15.5cm | 170.5 cm^{2} |