Respuesta :
You would need 2 unknowns for this problem since there are 2 types of trees. Let f = height of fir a tree and p = height of a pine tree. Now translate the words. The combined height of one fir and one pine tree is 21 meters. The equation would be f + p = 21 Four fir trees would be 24 meters taller than one pine tree. The equation would be 4f = 24 + p You have a system of equations. One way to solve this system would be to solve the first equation for p. This would give you p = 21 - f. Take the 21 - f and substitute it into the 2nd equation for p. This will give you 4f = 24 + 21 - f. Solving this equation, you would add f to both sides and combine 24 +21 giving you 5f = 45. Divide both sides by 5 and you get f = 9 meters. Thus the height of the fir tree is 9 meters. To find the height of the pine tree put the 9 meters back into the first equation (f + p =21) and you have 9 + p = 21. When you solve this equation you would find that p = 12 meters. CHECK: Put the 9 meters for the fir tree and 12 meters for the pine back into BOTH equations and see if BOTH are correct. f + p = 21 9 + 12 = 21 is correct 4f = 24 + p 4(9) = 24 + 12 36 = 36 is also correct The check works. So a fir tree is 9 meters tall and a pine tree is 12 meters tall. I don't know what the question was, but this might help.
Answer: Fir tree= 9, Pine tree= 12
Step-by-step explanation: Checked on khan
