We know that
If the scalar product of two vectors<span> is zero, both vectors are </span><span>orthogonal
</span><span>A. (-2,5)
</span>(-2,5)*(1,5)-------> -2*1+5*5=23-----------> <span>are not orthogonal
</span><span>B. (10,-2)
</span>(10,-2)*(1,5)-------> 10*1-2*5=0-----------> are orthogonal
<span>C. (-1,-5)
</span>(-1,-5)*(1,5)-------> -1*1-5*5=-26-----------> are not orthogonal
<span>D. (-5,1)
</span>(-5,1)*(1,5)-------> -5*1+1*5=0-----------> are orthogonal
the answer is
B. (10,-2) and D. (-5,1) are orthogonal to (1,5)
The factors of 4 are 1, 2, and 4 .
The factors of 9 are 1, 3, and 9 .
Jace bought 4 cookies and 2 brownies from the bakery.
Let x represent the number of cookies and y represent the number of brownies.
Since he bought $9 worth of cookies and brownies. Each cookie costs $0.75 and each brownie costs $3. hence:
0.75x + 3y = 9 (1)
Also, he bought twice as many cookies as brownies, hence:
x = 2y
x - 2y = 0 (2)
Solving equation 1 and 2 simultaneously gives x = 4, y = 2
Hence Jace bought 4 cookies and 2 brownies from the bakery.
Answer:166
Step-by-step explanation:438x.38=166
438 being the total amount of students
.38 being the 38% involved (moved percentage two to the left to make it a decimal)
