Answer: give me brainliest
Step-by-step explanation:
ax+by=a-b
ax=a-b-by
x=a-b-by/a←
bx-ay=a+b
substituting
b(a-b-by/a)-ay=a+b
ab-b²-b²y/a-ay=a+b
ab-b²-b²y-a²y/a=a+b
ab-b²-(b²+a²)y=a²+ab
-(b²+a²)y=a²+ab-ab+b²
(b²+a²)y=-(a²+b²)
y=-(a²+b²)/a²+b²
y=-1←
substituting value of y
x=a-b-b(-1)/a
x=a-b+b/a
x=a/a
x=1
Ok! So, given a quadratic function<span>, </span>y<span> = ax</span>2<span> + bx + c, when "a" is positive, the </span>parabola <span>opens upward and the vertex is the minimum value. On the other hand, if "a" is negative, the graph opens downward and the vertex is the maximum value. Now, let's refer back to our original graph, </span>y<span> = </span><span>x2</span><span>, where "a" is 1.
Hope this helps.</span>
12%= 0.12 = 12/100 = 108/900
1/10 = 90/900
2/9 = 200/900
108/900 + 90/900 + 200/900 = 398/900 used
900- 398 = 502
502/900 = 251/ 450
251/450 × 450 = 251
Karen has $251 for food
The last one is correct because 60+35+35+35=165
55+55+55=165