When flying faster than the speed of light, an airplane that flies parallel to the ground forms sound waves in the shape of a cone behind it. The waves intersect the ground in the shape of a hyperbola, with the airplane directly above the center of this hyperbola. If you hear a sonic boom along the hyperbola x^2/81 - y^2/4 = 1, what is the shortest horizontal distance you could be to the airplane?

show work please!!

Solve the equation 3x2 + 19x + 9 = 0 to the nearest tenth.

Jonathan pays $1.90 per pound for potatoes. he buys 8.3 pounds of potatoes. he determines that he will pay $15.77, before tax, for the potatoes. which best describes the reasonableness of jonathan’s solution? jonathan’s answer is reasonable because there are two decimal places in the factors and two in the product. jonathan’s answer is unreasonable because there are three decimal places in the factors and two in the product. jonathan’s answer is reasonable because is 16, and 16 is close to 15.77. jonathan’s answer is unreasonable because is 8, and 8 is not very close to 15.77.

Negative 5 1/12 + negative 4 1/4 + 6 3/4