Answer:
set mary is x years old, and helen is y years old.
first sentence:x=2y
second one:4(y-8)=x+4
bring x=2y in 4(y-8)=x+4
=>4y-32=2y+4
=>2y=36
=>y=18
=>x=36
mary:36
helen:18
Conic section (or simply conic) is a curve obtained as the intersection of the surface of a cone with a plane. The three types of conic section are the hyperbola, the parabola, and the ellipse. The circle is a special case of the ellipse, previously called the fourth type. Planes that pass through the vertex of the cone will intersect the cone in a point, a line or a pair of intersecting lines, called degenerate conics.
Answer:
5x+10y+5z
Step-by-step explanation:
Distributive Property means you multiply each component by the value you are distributing in this case: (1/2)(10x) + (1/2)(20y) + (1/2)(10z) which will yield 5x+10y+5z
