In triangle ABC, AB=15, BC=9, and AC=10. Find the length of the shortest altitude in this triangle.
Using Herons Formula,
sqrt(s(s-AB)(s-BC)(s-CA)) = sqrt(17(17-15)(17-9)(17-10)) = sqrt(17 * 2 * 8 * 7) = sqrt(1904) = 4√119
Then, you solve for the altitudes:
BC_a = (2 * A) / BC = (2 * 4√119) / 9 = (8√119) / 9
CA_a = (2 * A) / CA = (2 * 4√119) / 10 = (8√119) / 10 = (4√119) / 5
AB_a = (2 * A) / AB = (2 * 4√119) / 15 = (8√119) / 15
The shortest one is (8√119) / 15.
Using Herons Formula,
sqrt(s(s-AB)(s-BC)(s-CA)) = sqrt(17(17-15)(17-9)(17-10)) = sqrt(17 * 2 * 8 * 7) = sqrt(1904) = 4√119
Then, you solve for the altitudes:
BC_a = (2 * A) / BC = (2 * 4√119) / 9 = (8√119) / 9
CA_a = (2 * A) / CA = (2 * 4√119) / 10 = (8√119) / 10 = (4√119) / 5
AB_a = (2 * A) / AB = (2 * 4√119) / 15 = (8√119) / 15
The shortest one is (8√119) / 15.
Find the length of the shortest altitude in this triangle.
general circle equation
(x–xP)²+(y–yP)²=r²
y2=102−x2y2=92−(15−x)2y2=81−225+30x−x2100−x2=−144+30x−x230x=244xC=8.1¯33yC=hC=5.818
y2=152−x2y2=102−(9−x)2y2=100−x2+18x−81225−x2=19+18x−x218x=206xA=11.¯44yA=hA=9.697
y2=92−x2y2=152−(10−x)2y2=225−100+20x−x281−x2=125+20x−x220x=−44xB=−2.2yB=hB=8.726
The length of the shortest altitude in this triangle is hC=5.818
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