The wallace family had 100 relatives at their big dinner. of all the guests, 90 had french heritage, 80 had english heritage and 75 had native american heritage. at least how many had heritage from all three cultures?

Iam trying to solve a linear equation for the shoe size of someone 84" tall taking into consideration example 1 is 69" tall with a shoe size of 9 and example 2 is 72 inches tall with a shoe size of 11. i understand that the equation should be y=mx+b and that on the graph the answer is (3,2) but i just don't understand how to create the equation to solve for 84-inches and 60-inches tall questions. after two days, i need .

Two lines that do not intersect are skew. always sometimes or never

Which value is not a solution of 8x^3 – 1 = 0